Boris gets a guided tour of British culture from an expert on warm beer

IT WAS a secret serviceman's nightmare. At five past four yesterday afternoon Boris Yeltsin, one of the most powerful statesmen in the world, was knocking on the window of the Bernard Arms, Little Kimble, Buckinghamshire, seeking refreshment. The rose-coloured, ivy-clad pub had closed at 3pm but the President of the Russian Federation was not to be denied. He had been taking strenuous exercise, and in any case he was accompanied by John Major, the Prime Minister.

President Yeltsin, Mrs Yeltsin and John and Norma Major had just spent an hour working up a healthy thirst walking around the rolling countryside surrounding the Prime Minister's country residence, Chequers, where the Russian leader is spending the weekend during a visit intended to set Anglo-Russian relations on a new footing. Much of the time is being spent in relaxing country pursuits, but this morning will be devoted to discussions about Bosnia, bilateral trade issues and European Union relations with Russia.

The two leaders suddenly emerged into public view at around 3.30 yesterday afternoon on a public bridlepath in a field in the village of Ellesborough, followed by their entourage of anxious security men, and to the evident surprise of astonished villagers looking on.

Both men had changed from their grey suits into casual clothing for the afternoon's ramble. Mr Major blended into the country scene in a green Fair Isle sweater with green cords. Mr Yeltsin, in a loud blue tracksuit and white shirt, rather stood out. But they strolled side by side, swinging walking sticks, with wives following close behind, and when they eventually reached the Bernard Arms - whose sign, appropriately enough, is a bear - they piled in as a foursome, and sat down at a long table in the saloon bar. After the landlord had seen the wisdom of opening, that is.

Some dispute subsequently ensued as to what was drunk. A Number 10 source - perhaps remembering Mr Major's fond evocation of an England of warm beer (among other things) - said the men had a pint of bitter each. Pierre Gray, the pub's landlord, says it was a pint of lager. Mrs Yeltsin is thought to have had a half of something, and Norma Major a tomato juice.

Whatever it was, it worked. Half an hour later the party emerged refreshed and in a convivial mood. Mr Major had his arm around Mrs Yeltsin, and President Yeltsin had his arm around Norma Major - all four were beaming widely.

Let us hope that the two leaders did not look too closely at the pub's walls, decorated with landscape prints and photographs.

One of them bears a photograph of a former inhabitant of Chequers, Harold Wilson, enjoying a drink with his wife Mary and labrador Paddy. It is dated Sunday April 3, 1976 - his last full day as prime minister before his resignation.

It might have put the Prime Minister and the President off their pints.