Let’s do a Brexit deal with the Parthenon marbles

Geoffrey Robertson ('Let’s do a Brexit deal with the Parthenon marbles' Guardian Tuesday 4 April 2017) suggests that gestures involving the enhancement of Europe’s cultural heritage may have a role to play in ensuring a modicum of success in Brexit negotiations:

The most important symbols of Europe’s cultural heritage are the Parthenon marbles. Half of them are in the new Acropolis Museum, while the other half, ripped off the Parthenon by a Scottish diplomat, sit in a British Museum gallery [...] There is no more significant cultural heritage than the Parthenon marbles, so the negotiators on both sides are bound to take their reunification into account. They are, of course, priceless, and a UK offer to return them should be accepted in return for major concessions [...] a willingness to surrender Elgin’s ill-gotten gains will win goodwill as well as concessions. Britain is leaving Europe, so it should leave Europe with its marbles.