Human rights groups say the number of dissidents in Burmese jails has nearly doubled to more than 2100 over the past year and called on the United Nations to act to free the prisoners.

A report from the Assistance Association for Political Prisoners and the United States Campaign for Burma says there are now at least 2123 political prisoners in the country, up 78 per cent on the UN's figure of 1192 in June 2007.

It comes after UN High Commissioner for Human Rights Navi Pillay called last week for the release of Burma's political prisoners.

Former political prisoner Bo Kyi said, ''By nearly doubling the number of political prisoners, the Burmese regime is directly defying the United Nations. Yet the UN is paralysed because the Secretary General is still reluctant to call on China to work together with other members of the Security Council to secure the release of all prisoners by the end of December.''

China, a veto-wielding permanent member of the UN Security Council, is a close ally and economic partner of Burma and opposes interference in its affairs.

The two groups responsible for the report sent an open letter yesterday to UN Secretary General Ban Ki-moon urging action to secure the prisoners' release.

On September 23 the regime announced an amnesty, releasing more than 9000 prisoners ahead of elections planned for 2010 but only 10 of them were political prisoners. AFP