PHNOM PENH - Myanmar's detention of opposition leader Aung San Suu Kyi has hurt the image of Southeast Asia's regional group and strained its policy of quiet diplomacy, ASEAN chief Surin Pitsuwan said on Wednesday.

The organization is mindful of the fact it does not want to interfere in the internal affairs of any member state, Surin, secretary-general of the Association of Southeast Asian Nations (ASEAN), told reporters in Phnom Penh.

But when those issues affect the efficiency, the profile and the confidence in the organization, it (concern) has to be expressed, he said on the sidelines of an ASEAN-European Union ministerial meeting.

It is an issue that also affects ASEAN's image and collective interests. Therefore it is being expressed ... this concern and anxiety that the organization feels and what it feels from around the world, he said.

His comments come after U.S. President Barack Obama on Tuesday demanded the immediate and unconditional release of Suu Kyi, and followed a call from Asian and European foreign ministers in Hanoi for an end to detentions and political restrictions.

Suu Kyi, one of more than 2,000 political prisoners in Myanmar, has been incarcerated for more than 13 of the past 19 years. The country's generals have so far ignored calls for her release and threats of tougher Western sanctions.

Suu Kyi, 63, is charged with breaking the terms of her house arrest after an uninvited American intruder, John Yettaw, swam across a lake to her Yangon home on May 4. Her two female assistants and Yettaw are also on trial.

Although her house arrest has been lifted, she remains in detention and faces five years in jail if convicted.

INTERNATIONAL OUTRAGE

The trial has sparked international outrage and critics say the charges are trumped-up to silence Suu Kyi until after a multi-party election in the former Burma in 2010.

It comes at a time when the United States, Europe and ASEAN are trying to figure out a new strategy toward Myanmar's generals after years of sanctions have done nothing to change

Surin said the international outcry and ASEAN's stance had been registered by Myanmar's foreign minister, Nyan Win, whom he said gave no indication as to how the junta would respond.

Thai Foreign Minister Kasit Piromya defended his country's decision, as holder of the rotating ASEAN chair, to issue a statement saying the trial threatened Myanmar's honor and credibility.

(The statement) is not condemnation, interference and violation of Myanmar's sovereignty because ASEAN is the same family, Kasit told reporters.

Marcin Majewski, head of the EU's Asian policy unit, said Suu Kyi's release was vital for the country's democratic future.

The process must start with the full release of Suu Kyi and allowing all parties in Myanmar to actually participate in a process that will lead to establishment of democracy, he said.

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