UK Treaties

Guidance to the work of the Foreign and Commonwealth Office (FCO) Treaty Section


The FCO Treaty Section supports government departments with advice on practice and procedural matters relating to the conclusion of treaties by the UK.

We also provide information on those treaties to which the UK is, or has been a party, including the UK Treaties Online (UKTO) service which is available to all users free of charge.

Our team performs a range of activities, including:

  • advising on UK treaty practice and procedure including preparation of treaty texts, instruments of ratification and Full Powers (authority to sign treaties on behalf of the UK)
  • publishing UK treaties as Command Papers with Explanatory Memoranda (EMs)
  • registering with the United Nations details of treaties that have entered into force for the UK

This document is a guide to some of the important elements of the UK’s treaty practice and procedure. It provides a link to UKTO, an interactive database enabling users of this site to research details of bilateral and multilateral treaties applying to the UK and contact details for an enquiry service which can help explain or clarify information on treaties applying to the UK.

UK Treaties Online

The UKTO service enables you to access details of over 14,000 treaties involving the UK. You can research the existence of treaties, find important information about them (such as the place and date of signature and entry into force date) and see which states or organisations participate in them.

Treaty texts

The UKTO database contains records of treaties published since the nineteenth century and links to their texts published as Command Papers in the UK Treaty Series from 1892 to present. Non-Treaty Series command papers published up to 2012 can be found on the archived version of our website (updated to 31 December 2012). The texts of most treaty Command Papers irrespective of Series can also be found on the UK Parliamentary Papers site.

UKTO guidance notes

We recommend that you take time to read the guidance notes as presented on the home page.

Treaty Enquiries Service

Treaty Information Section maintains records of treaties involving the UK stored on a database which supplies information to UKTO. Electronic treaty records were introduced in 1987, and prior to that date were stored in manual registers and other physical formats. The electronic database records are continually updated and provide the basis of our Treaty Enquiries Service which is able to provide advice on treaties which involve the UK and its Crown Dependencies and Overseas Territories. Treaty Information Section also holds historical indexes and finding aids.

It should be noted that Treaty Section staff are not able to provide an interpretation of a treaty, or advise on its applicability to a particular situation. We can however generally advise on whether a treaty has entered into force, details of the signatories and contracting parties, together with dates of signature, ratification, approval, acceptance, accession, succession and withdrawals or denunciations. Reservations, declarations or objections can usually be identified, and where applicable, the depositary.

Treaty texts published in the UK Treaty Series from 1892-present can be found by searching the UKTO database. All treaties regardless of series published since 1997 are also available on our site.

In the case of multilateral treaties for which the UK is not the depositary, it is recommended that their current status is cross-referenced with the depositary government or authority (see also following section on The UK as a depositary).


The Treaty Enquiries Service is available from 0900 to 1700 Monday to Friday.

Telephone: 020 7008 1109


Practice and procedures

The responsibility for concluding treaties involving the UK lies with the Secretary of State for Foreign and Commonwealth Affairs. The FCO is responsible for Foreign and Commonwealth policy aspects of all treaties, as well as for dealing with questions of form and procedure. It must also consider points of international law. This remains the case even when the negotiation of the treaty is led by another government department, ie the department that will carry out the treaty’s provisions.

The FCO’s Legal Advisers and Treaty Section must be given the opportunity to comment on the drafts of all treaties under negotiation in order to ensure that they are drafted in accordance with correct practice.

Our Treaty Procedures staff produce original signature copies of treaties that are to be signed by the UK either in London or overseas. This involves advising officials, both within FCO and in other government departments, on the form the treaty should take and related matters such as the production of Full Powers and instruments of ratification. Once the terms of the treaty have been agreed, the original document is produced by Treaty Section staff on special treaty paper and is then bound and sealed into a binder.

Advice is also provided on the form that the treaty signing ceremony should take and, where possible, Treaty Section staff will attend the signing of a treaty in the UK.

Where the treaty is to be signed overseas, Treaty Section staff will still advise on its form and production and on any procedures that should be followed for the signing ceremony. However, it would not be usual for a member of Treaty Section staff to attend an overseas signing.

Our Treaties and MoUs (Memoranda of Understanding): Guidance on Practice and Procedures document gives you further information.

After signing, Treaty Section staff arrange for the agreement to be printed and laid before Parliament.

Publication of treaties

Since 2010 it is a statutory legal requirement for the government to lay treaties which the UK has signed subject to ratification or its equivalent, or to which it intends to become party by accession, before both Houses of Parliament. Treaties laid before Parliament are in the form of a command paper, which is published in one of three FCO series:

  • Country Series – for bilateral treaties
  • Miscellaneous Series – for multilateral treaties
  • European Union Series (formerly the European Communities Series prior to 1 April 2011) – for treaties between member states or between member states and non-member states or group of states.

Agreements entered into by the EU which are subject to national ratification or its equivalent and amendments to multilateral treaties which require new legislation are also laid before Parliament. Such treaties are required to be laid before the UK indicates its formal consent to be bound and therefore provides Parliament with an opportunity to scrutinise treaty provisions before this occurs. However, this practice does not apply to the following types of treaties:

  • a treaty covered by Section 12 of the European Parliamentary Elections Act 2002
  • a treaty covered by Section 5 of the European Union (Amendment) Act 2008
  • a treaty for which an Order in Council may be made under Section 158 of the Inheritance Act 1984, Section 2 of the Taxation (International and other Provisions) Act 2010 or Section 173 of the Finance Act 2006
  • a treaty concluded (under authority given by the Government of the United Kingdom) by the Government of a British Overseas Territory or any of the Channel Islands or the Isle of Man.

Once a treaty has entered into force for the UK (that is become legally-binding in international law), it is our practice to publish the text in the form of a Command paper in the Treaty Series. Where a treaty has been previously laid before parliament prior to ratification or accession, it is re-laid upon entering into force. Where a treaty has entered into force on signature alone, it is laid for the first and only time in the Treaty Series.

Treaty Command Papers

Texts of Treaty Command Papers laid before Parliament in the Country, Miscellaneous, EU Series (with EMs) from 1997 to 2012, and in the Treaty Series from January 1999 to December 2012 are available on our archived site.

Click on the links below for access to Command Papers in the respective Series laid before Parliament from 2013 to present:

Country Series Bilateral Agreements that are not yet in force
European Union Series Multilateral Agreements between Member States of the European Union, or between Third Parties and Member States of the European Union that are not yet in force for the UK. (Note: On the 1st April 2011, the European Union Series replaced the European Communities Series)
Miscellaneous Series Multilateral Agreements, where the UK is a signatory, that are not yet in force
Treaty Series 2013 - 2017 Agreements that have completed all necessary procedures and now are in force for the UK
Treaty Series 2018 to present  

Treaties and the Constitutional Reform and Governance Act (CRaG Act)

CRaG details the procedures for the ratification of treaties and puts parliamentary scrutiny of treaties on a statutory footing. The Act received Royal Assent on 8 April 2010 and was brought into force on 11 November 2010 by a Statutory Instrument that was laid before Parliament. Under the Act all treaties (except those listed above) which are subject to ratification, acceptance, approval, the mutual notification of completion of procedures, or to which the UK intends to accede, cannot be ratified unless they have been laid by a Minister of the Crown before parliament for 21 sitting days without either House having resolved that it should not be ratified. The Act details the procedures required if either House resolves that a treaty should not be ratified.

Since 1997, when a treaty is laid before Parliament it is accompanied by an Explanatory Memorandum (EM) which explains the provisions of the treaty and the reason for seeking ratification.

When a treaty Command Paper is laid before Parliament it is sent together with its accompanying EM to the relevant department Select Committee in the House of Commons.

When a treaty enters into force for the UK (whether this is on signature or following ratification, accession etc), it is published again in the Treaty Series of command papers and laid before Parliament. The EM is then linked to the Treaty Series document.

Prior to the introduction of the CRaG Act, all treaties (other than the exceptions as above) that were subject to ratification, acceptance, approval, the mutual notification of completion of procedures or to which the UK intended to accede, were laid before Parliament under the Ponsonby Rule.

United Kingdom treaty action bulletins

Treaty publication news, UK actions on multilateral treaties and changes to the status of treaties for which the UK is depositary can be found in the UK treaty action bulletins.

UN Registration

Treaties to which a member state of the United Nations becomes a party must be registered with the UN, under Article 102 of the UN Charter, in all their languages and with all their ancillary documents. The intention of this requirement is to discourage secret treaties.

In theory, no member state may invoke a treaty before the International Court of Justice or any other organ of the UN unless the treaty has been registered. Regulations to give effect to Article 102 were adopted by the General Assembly on 14 December 1946, and have been modified several times since.

Treaties are subsequently published by the UN, both on the internet and on paper, in the United Nations Treaty Series.

FCO Treaty Section is responsible for the registration of:

  • all bilateral treaties concluded by the UK which have been published in the UK Treaty Series and have therefore entered into force
  • multilateral treaties of which the UK is depositary, when they have entered into force, whether or not the UK is a party

Other multilateral treaties are registered by the organisation or foreign state with which they are deposited.

UK overseas territories

Unless expressly authorised to do so by HMG in the UK, overseas territories (OTs) do not have the authority to become party to treaties in their own right. The UK must extend the territorial scope of its ratification of treaties to include them. This is normally done either at the time of ratification, or at some later date. When the UK is involved in the negotiation or signature of any treaty which could apply to the OTs it is important that they are fully consulted at the earliest stage. The OTs must then be allowed a proper length of time to consider the implications of having any treaty extended to them. Further guidance on this issue is produced by the Ministry of Justice.

We have published complete guidance on extension to treaties on overseas territories.

The UK as a depositary

The UK acts as depositary for multilateral treaties encompassing a wide range of subjects.

As part of this function, Treaty Section is responsible for co-ordinating the UK’s response to formal instruments of ratification or accession to these treaties which are deposited with the FCO by foreign governments. Part VII of the Vienna Convention on the Law of Treaties contains provisions on the role of depositaries.

In most cases, treaties take effect for a new state party either on the day an instrument is deposited with the FCO, or after a pre-determined period of time has elapsed in accordance with the provisions of the treaty concerned. The date the instrument is received within the FCO is therefore crucial, as it determines the precise date from which a state is bound by international law to exercise the rights and obligations that the treaty provides.

Governments and other international organisations wishing to deposit an instrument of ratification or accession with the FCO by post should ensure that it is sent to the following address, and clearly marked:

Treaty Section
(Legal Directorate)
Room WH.2.143
King Charles Street
Foreign and Commonwealth Office

Requests for heads of mission (in London) to deposit instruments of ratification or accession with the FCO personally should be addressed to the Head of Treaty Section at the above address.

It should be noted that while Treaty Section can provide publication references to treaties and links to texts of treaties for which the UK is depositary, it is unable to supply certified copies of treaty texts on demand. Texts can be accessed on UKTO or purchased from The Stationery Office Ltd. Copies of older treaties may be found in library reference collections and photocopies of out-of-print items can be purchased from the British Library. Original copies of treaties deposited at The National Archives (TNA) may be identified in the TNA’s catalogue.

Lists of treaties

We are frequently asked to provide lists of treaties that may apply in certain circumstances, or to defined territorial areas. For ease of reference, we have reproduced various lists in the archived FCO Treaties website pages covering:

Please note any information provided is for convenience only, and is based on information supplied by the depositary concerned. Treaty Section accepts no responsibility for any inaccuracies or omissions contained therein. It is recommended that status information be confirmed with the depositaries for each agreement.


The FCO is not responsible for the contents or reliability of the linked websites, and does not necessarily endorse the views expressed within them. Listing shall not be taken as endorsement of any kind. We cannot guarantee that these links will work all of the time and we have no control over availability of the linked pages.

Published 2 July 2013
Last updated 4 October 2013 + show all updates
  1. Added list of countries that have ratified the Vienna Convention on Consular Relations.
  2. First published.
  3. added April 2013 bulletin of recent changes to UK treaties in force
  4. Added latest editions of the supplementary list.
  5. added treaty command series papers in a table with links to the 4 document series.
  6. contact details for enquiries service added