The United States and Britain have warned Iraq that they will not tolerate any interference with their aircraft patrolling the no-fly zones in the north and south of the country.

The warning came after the Iraqi vice-president, Taha Yassin Ramadan, said Iraq did not recognize the no-fly zones and would fire on any planes violating its airspace.

Mr Ramadan said it was the right moment to challenge the air patrols which have been carried out since the end of the Gulf War in 1992.

A National Security Council spokesman in Washington said American pilots could act in self-defence whenever they felt threatened and the defence ministry in London said all aircraft operated under rules of engagement that allowed the return of fire.

On Saturday a British Tornado crew flying over southern Iraq reported seeing anti-aircraft fire, but did not consider it close enough to amount to a threat.