Mr Cook also said there could be no lifting of sanctions while Saddam Hussein retained weapons of mass destruction.

Mr Cook was speaking during the Commons foreign affairs and defence debate on Friday, following from the Queen's Speech earlier this week.

"If he really wants to see an end to sanctions, then the only way he is going to get it is by giving full cooperation to the UN inspectors," he told MPs.

The foreign secretary said British forces were still in place in the Gulf. "If UNSCOM is prevented from inspecting suspect sites, then military action can be swift," he added.

"As UN Secretary General Kofi Annan has warned, next time there may be no diplomatic phase.

"Saddam must understand that there can be no question of lifting sanctions while he retains the weapons of terror that could wipe out whole cities throughout the region."