By Nyta Mann BBC News Online political correspondent

Detailed choreography ensures it is extremely rare for encounters between world leaders to ever go off the diplomatic rails.

But when the mask does slip, the resulting picture of how things really are - even if only briefly glimpsed - often reveals far more than a thousand end-of-summit "communiques".

Margaret Thatcher: "I want my money back"

That the subject of Britain's rebate was involved in the bust-up between Tony Blair and Jacques Chirac is highly fitting, since one of the most famous castings-aside of diplomatic niceties on the Euro-stage is Margaret Thatcher's 1984 handbagging of her fellow EU leaders.

The then Mrs Thatcher, uncompromising in her demands that "I want my money back!", secured the special deal by which the UK gets a rebate on its contribution to the EU budget at a bitter meeting in Fontainebleau.

The episode swiftly became seen as a thumbnail guide to her political character.

Kruschev's shoe

In 1956 a British prime minister was on the receiving end. It was a speech to the United Nations by Harold Macmillan that Soviet President Nikita Kruschev famously interrupted by beating his shoe against his desk before shouting to the US representatives "We will bury you".

Macmillan, in keeping with his reputation for unflappability, responded to the highly irregular shoe-banging with: "I shall have to have that translated!"

Nixon's 'kitchen debate'

A later Cold War instance of departing from the diplomatic script, again featuring Kruschev, is the notorious 1959 "kitchen debate" between the Soviet leader and Richard Nixon.

Richard Nixon: Kruschev gave him as good as he got

During a visit to the kitchen-set of an American exhibition in Moscow, Nixon supposedly privately berated the Soviet leader during a break in the formal itinerary.

Neither man spoke the other's language, but photographs of Nixon stentoriously wagging his finger in Kruschev's face did the US vice president no harm back home.

The effect was, however, spoilt when it subsequently emerged that far from listening meekly, Kruschev responded to Nixon's finger-wagging by telling him - in Russian - to "Go screw my grandmother".

'President Yeltsin is unwell'

Connoiseurs of undiplomatic behaviour are spoilt for choice when it comes to Boris Yeltsin. But who can forget his failure to even leave the plane when, in October 1994, the Russian President arrived in Ireland for an official visit?

As Albert Reynolds, assorted other dignitaries, a guard of honour, cameras and the world's press waited on the runway at Shannon Airport, increasingly embarrassed members of the Russian entourage could only repeatedly claim he was variously "unwell" and "too tired".

Boris Yeltsin: Never made it off the plane

He never set foot on Irish soil - and on arriving back in Moscow appeared in cheery health, claiming his bodyguards had just failed to wake him.

Later revelations from a disillusioned ex-Yeltsin bodyguard only muddied the waters by alleging the Russian leader was indeed drunk much of the time but that on this occasion he had actually passed out with a suspected heart attack.

'Macho' Prescott

A more recent on-stage spillage of sentiments usually kept under wraps came in 2000 when the French environment minister, Dominique Voynet, accused John Prescott of behaving like an "inveterate macho" and in a "really pathetic ... shabby" manner.

It was a riposte following the deputy prime minister's blaming of Mme Voynet for the collapse of the environment summit in The Hague.

The normally gallant Mr Prescott had complained that she scuppered a deal on climate control because she had "cold feet" and was too tired to understand the talks.