It was made by a leading London goldsmith and was once used as a trophy for the Doncaster Cup horse race - but could now be exported abroad.
This George II silver-gilt ewer and basin is the only known example of its kind from the 1730s combining classical and rococo design in such a lavish way.
Culture Minister Ed Vaizey has today placed a temporary export bar on the items, known as the Bristol ewer and basin, providing a last chance to raise the money to keep them in the UK.
The Minister’s ruling follows a recommendation by the Reviewing Committee on the Export of Works of Art and Objects of Cultural Interest on the grounds of their aesthetic importance and significance to the study of British silverware.
“The ewer and basin are wonderful, unique objects,” Committee member Philippa Glanville said. “They really demonstrate the extraordinary skill of goldsmiths in eighteenth century London, and the influence that they had on the design of British silver over the next 200 years.”
The items were given as a gift by the Corporation of the City of Bristol to Judge John Scrope, a significant figure in early eighteenth century English society, in recognition of his services to the city.
In 1876 they were supplied for use as a trophy for the Doncaster Cup, and the basin is marked with the coat of arms and initials of the owner of the winning horse.