DT: Thailand: double taxation agreement, Article 2: Taxes covered
(1) The existing taxes which are the subject of this Convention are:
(a) in the United Kingdom:
(i) the income tax;
(ii) the corporation tax;
(iii) the capital gains tax;
(iv) the development land tax; and
(v) the petroleum revenue tax;
(hereinafter referred to as `United Kingdom tax`);
(b) in Thailand:
(i) the income tax; and
(ii) the petroleum income tax;
(hereinafter referred to as `Thai tax`).
(2) The Convention shall also apply to any tax which is subsequently imposed by either Contracting State in addition to, or in place of, the existing taxes provided that it is agreed by the competent authorities of the Contracting States to be identical or substantially similar to the taxes existing at the date of signature of the Convention. The competent authorities of the Contracting States shall notify each other of any changes which are made in their respective taxation laws.