Most of the surviving leaders of the seven-month long 1988 uprising - the biggest challenge to army rule stretching back to 1962 - were arrested last August at the start of fuel-price protests that grew into anti-government demonstrations.

They remain behind bars along with an estimated 1,100 political prisoners.

Protests

Outside the South-East Asian nation, however, human rights groups and activists who fled the crackdown on the 1988 protests planned demonstrations at Myanmar and Chinese embassies.

The latter are being targeted on what is also the opening day of the Beijing Olympics because of China's commercial and diplomatic ties to the generals, gate-keepers of Myanmar's plentiful reserves of natural gas and other resources.

But protests were likely to be muted in Singapore, which has also been accused of supporting Myanmar's military government for business opportunities.

Myo Myint Maung, a Myanmar national, said at least three activists who were involved in an illegal protest last year against Myanmar's military government, had been forced to leave Singapore after their visas were not renewed.

A Singapore interior ministry spokeswoman said "foreigners who work or live here are expected to at least respect the law and local sensitivities".

On Thursday, George Bush, the US president, used a visit to neighbouring Thailand, home to more than 100,000 Myanmar refugees and more than a million migrant workers, to call again for the release of Aung San Suu Kyi, the opposition leader and Nobel laureate.

"The American people care deeply about the people of Burma and dream for the day the people will be free," he told dissidents and former political prisoners at an hour-long lunch.

However, Bush also heard criticism of Washington's stance towards Myanmar, formerly known as Burma, for forcing the generals into isolation.

Aung Naing Oo, a former student activist who fled for his life 20 years ago, said he asked Bush "to engage with the Burmese military".

"It's only Than Shwe and a few other generals who want to isolate Burma, so I told him engagement was very important," he said.

Cyclone devastation

Meanwhile, The Associated Press reported that conditions in Myanmar's Irrawaddy delta that was devastated by Cyclone Nargis in May, were far worse than the government and even the UN said.

Three months after a disaster that claimed nearly 140,000 lives, thousands of villagers are still getting little or nothing from their government or foreign aid groups, AP reported.