Britain at the UN: Clegg pledges coalition is to restore Britain's reputation tainted by Iraq

Addressing the UN general assembly in New York, the Deputy Prime Minister will say that Britain has learned "the hard way" that democracy "cannot be created by diktat".

His remarks are likely to be seen as a reference to the consequences of the invasion of Iraq, which he has previously described as "illegal", although he may not refer to the war directly.

"Britain will stand as a beacon of democracy, freedom and law," he will say. "Many of the values that must be at the heart of a new global settlement are in our national DNA – tolerance, fairness, democracy, equality before the law.

"But our approach will also be hard-headed and realistic. In recent years, we have learned – sometimes the hard way – that democracy cannot be created by diktat. Freedom cannot be commanded into existence.

"The new coalition Government, now five-months-old, will restore Britain's international reputation by pursuing a hard-headed foreign policy based on liberal values."

Aides said his comments to the UN, where he is standing in for Prime Minister David Cameron, are intended to convey a general point about international law.

His appearance before the UN today comes after meetings with his US counterpart Joe Biden.

Prior to the lunch appointment yesterday, he dismissed suggestions Washington was troubled by the coalition's cuts programme.

"Each country needs to take its own decisions according to its own circumstances," he said.