The EU added an "Elgin Marbles clause" to its demands for a post-Brexit trade deal with Britain on Tuesday, raising fears that the move would bolster Greek calls for their repatriation to Athens.

The demand was revealed in Brussels after EU inter-governmental talks and as Michel Barnier rejected demands by David Frost, the UK's chief negotiator, for a Canada-style trade agreement.

British negotiators will reject any role for the European Court of Justice (ECJ) in the future trading relationship, it emerged, opening another rift between the two deeply divided sides ahead of trade talks next month.

EU governments have been revising the mandate for the negotiations, which is meant to be finalised on Wednesday.

The latest draft, a copy of which was obtained by The Telegraph, reads: "The Parties should, consistently with Union rules, address issues relating to the return or restitution of unlawfully removed cultural objects to their countries of origin."

One official said the clause – demanded by Greece, Cyprus, Spain and Italy – was understood to refer to the Marbles, a collection of sculptures, inscriptions and architectural features which originally formed part of the Parthenon temple and other structures on the Acropolis in Athens. They were acquired by Lord Elgin between 1801 and 1805.