To lose one valuable canvas might be regarded as a misfortune. To lose two looks like carelessness. But to lose track of at least 50 seems like downright incompetence, especially during a period when the nation’s art budget has had to tighten its belt.

Culture has long fulfilled an important diplomatic function, from medieval times, when a monarch would dispatch an artist to paint a picture of a potential bride, right through to the Cold War, when exchanges of musicians or dancers helped to maintain contact between the Soviet Union and the United States. It has served as an instrument of seduction, of enticement, of persuasion. It has been used to build bridges and promote mutual dialogue.

That is why our embassies all over the world are invited to draw from a government-owned art collection of 1,200 pictures to decorate their walls. Landscapes – as well as standard and often slightly dusty reproductions of a Pietro Annigoni portrait of the Queen – provide an eclectic and not-too-expensive range of mementoes of Dear Old Blighty. That is how W. D. Adam’s painting of the Berkshire Downs found its way to British Honduras or Henry Rolfe’s Salmon and Trout came to be in Lahore. Patriotic pride and sentimental reminder meet in works that are mostly fairly indifferent but, with time, increasingly valuable.

And then they go missing – and who notices amid the constant chaos of the many ambassadorial moves? Who knows if that ghastly still life may still be somewhere in the basement, consigned there by an impetuous ambassadorial wife, or if some staff member took a fancy to that sunset and slipped off with it a decade ago. Once they have gone they are all but impossible to trace. This, after all, is not the cream of the collection. It is not the Constable. And who in Guyana is going to recognise Carel Weight’s Grantley Hall Through the Trees, even if they come across it?

What’s the answer? Maybe the focus of the diplomatic art display should shift. Instead of impressing our imported culture on those we are visiting, we should try to improve our own cultural understanding by inviting local artists to show their work. It might not only forge a more cordial entente but it could, as one Swiss ambassador discovered, prove lucrative.

A few years ago Switzerland was in the headlines for all the wrong reasons when its banks refused to give up Nazi gold. So the Swiss Ambassador to London invited a gang of young graffiti artists down to his underground car park to indulge in a bit of spray-painting in the hope of imparting the message that the Swiss were cool.

Among the works were several by Banksy. Whose graffiti pieces now sell for tens of thousands of pounds.

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