Russia and China also hailed the move, with the former saying it was urging Baghdad to fully comply with the inspections -- though stressed it was opposed to unilateral action by the United States. 

Iraq's ambassador to the United Nations, Mohammad Al-Douri, delivered the acceptance of a resolution ordering the inspectors to return in a letter to the U.N. 

"Iraq has now taken the first step," said Straw. "I welcome that. 

"But we must remain vigilant. Iraq's intentions are notoriously changeable." 

The next step was for Iraq to provide an accurate, full and complete declaration of all aspects of its biological, chemical and nuclear weapons programmes by December 8, Straw said. 

"Let there be no doubt that any failure by Iraq to comply with its obligations will lead to serious consequences. 

"For it is only the credible threat of force which has brought Iraq this far today." 

Russian Deputy Foreign Minister Yuri Fedotov said he wanted the U.N. weapons inspectors back in Iraq as soon as possible, CNN's Moscow bureau chief Jill Dougherty reported. 

"The language of the resolution is rather harsh, so the emotions it can stir in Iraqi society are understandable," Fedetov told a news conference. 

"But we still hope the Iraqi leadership will come up with a pragmatic approach and take into account that the resolution does not include a clause on the automatic use of force." 

Dougherty said Moscow has been pushing Baghdad to accept the resolution saying "this is your best chance." 

But Fedotov voiced concerns as to what would happen during the weapons inspections -- what would happen if the weapons inspections were interfered with, what would happen if something lesser happens like a tyre blew on one of the U.N. inspection vehicles. 

"Those things will have to be evaluated, the Russians believe, by the U.N. and by the weapons inspectors who will give their reports to the United Nations," Dougherty said. 

"One thing the Russians are really hoping to avoid is unilateral action by the U.S. -- Russians don't want it and they really think these things can be dealt with through the United Nations." 

Meanwhile, China's deputy U.N. ambassador, Yishan Zhang, who holds this month's Security Council presidency, said the 15-member body welcomed "the correct decision of the Iraqi government." 

"We want to see the resolution implemented fully and very effectively," he told Reuters. 

Reaction is awaited from leaders of other nations including French President Jacques Chirac.