Already under pressure from both the Association of Southeast Asian Nations and the United States over its failure to move towards democracy, Burma's military junta has adjourned a convention aimed at drawing up a new democratic constitution.

Burmese officials blamed rising temperatures and the approaching monsoon for suspending its constitutional convention Thursday, and said the talks would not resume until November at the earliest.

A new constitution is therefore unlikely to be in place before Burma is scheduled to take the chair of the 10-member Association of Southeast Asian Nations in mid-2006, analysts say.

The announcement came as ASEAN governments were struggling with a growing disagreement over how to deal with Burma's military government.

A group of Malaysian lawmakers began moves last week to deny Burma its turn as ASEAN chair next year, unless its government made concrete moves towards democracy.

Further pressure was added Thursday when U.S. Republican Senator Mitch McConnell called for the United States, Europe and the "community of democracies" to boycott all ASEAN meetings if Burma was in the chair.

The Thai Foreign Ministry spokesman, Sihasak Phuanketkeow, replied that further isolation of Burma, also known as Myanmar, was not the answer.

"We believe that to bring about further progress [in Burma] the path should be of constructive engagement and constructive dialogue," said Sihasak Phuanketkeow. "We don't think that further isolation of Myanmar would achieve the common objective that we share."

There was no unanimity within ASEAN. Lawmakers in the Philippines have also called for Burma to be denied the chair unless reforms are carried out.

Singapore Prime Minister Lee Hsien Loong, on an official visit to Burma Wednesday, was reported as telling government leaders that developments in their country could affect ASEAN as a whole.

But Cambodian Prime Minister Hun Sen said Thursday that the matter was Burma's internal affair, and he refused to back any campaign to prevent Burma from chairing ASEAN.

And Malaysia's government distanced itself from its activist legislators on Thursday, saying it, too, would not push to deny Burma the chair in 2006.

The United States and Europe have imposed sanctions on Burma in an effort to force reform, but Gary Rodan, an Asia specialist at Australia's Murdoch University, says the Western nations could face diplomatic problems if Burma does take over the chair.

"It would be a bit of an embarrassment for the Americans if a group of countries that have worked closely with the Americans in executing the security policies in the region were to be involved with an organization which had its meetings chaired by Burma," said Gary Rodan.

Burma's military has been in power for more than 40 years, and shows no sign of relinquishing power, despite widespread international support for the opposition National League for Democracy and its detained leader, Aung San Suu Kyi.