The security council statement, which also called for "genuine dialogue" with the opposition leader, Aung San Suu Kyi, marked the first time that Beijing had agreed to UN criticism of the junta.

The statement did not threaten sanctions, but the significance of its unanimous support by all 15 members of the security council would not have been lost on Burma's generals, who had hitherto been able to count on China, a neighbour and key trading partner, to block UN censure.

"That represents a very significant shift in global politics from just a few weeks ago," said the foreign secretary, David Miliband. "It is proof that the recent brutal crackdown and ongoing persecution of peaceful protesters has isolated the Burmese regime. They must now respond to these growing global calls for them to work with others in building a better future for the people of Burma."

Britain co-sponsored the statement with the US and France, which also signalled they would maintain the pressure on the junta to respond to UN demands for the release of prisoners, including Ms Suu Kyi.

The US ambassador to the UN, Zalmay Khalilzad, said that if the junta failed to respond accordingly, the security council would take the matter up again in as little as two weeks. "We will not relent. We will persist," he told journalists.

"What is important is that the government of Myanmar delivers," France's deputy UN ambassador, Jean-Pierre Lacroix, said.

China's deputy UN ambassador, Liu Zhenmin, did not respond to questions on what further action the council might take, saying only that he hoped the statement would contribute to the success of a mission to the region by a UN special envoy, Ibrahim Gambari, due to start next week. Mr Gambari will visit Thailand, Malaysia, Indonesia, India, China and Japan, before going to Burma by the end of the month.

The statement had to be diluted from earlier drafts to win Chinese approval, dropping a demand for the Burmese government to account for what had happened to detained demonstrators, and a call for a transition to democracy.

A Burmese dissident group yesterday accused the security forces of beating and killing protesters, and leaving them to die of their injuries. The Democratic Voice of Burma, a Norway-based radio station run by dissident journalists, said at least a dozen freed prisoners had given accounts of brutal treatment in detention centres. One said that "dozens" of prisoners had been killed.

The government has said that 10 people were killed and nearly 2,100 arrested in the course of last month's street demonstrations, and that 700 detainees had since been released.

The regime has denied torturing its prisoners and has blamed the protests on western instigation. The state-owned New Light of Myanmar newspaper denounced the protesters, as "stooges of foreign countries putting on a play written by their foreign masters".