President Bush says he plans to call attention to the human rights situation in Burma at this week's annual 21-member Pacific Rim summit in Australia.
Mr. Bush slammed the Burmese military government's most recent crackdown on peaceful protests as "inexcusable".
President Bush says he is looking forward to speaking out about Burma at the annual meeting of the Asia Pacific Economic Cooperation forum.
"It's inexcusable that we've got this kind of tyrannical behavior in Asia. It's inexcusable that people who march for freedom are then treated by a repressive state. And those of us who live in comfort of a free society need to speak out about these kind of human rights abuses."
The president spoke at a news conference in Sydney after talks with Australian Prime Minister John Howard.
He said he wants to speak for all the people of Burma - including their jailed Nobel laureate pro-democracy leader.
"And so, Mr. Prime Minister, I hope you don't mind me speaking as clearly as I possibly can about the fate of Aung San Suu Kyi and her friends, and average citizens who simply want the same thing we have, to live in a free society."
Aung San Suu Kyi has been under some form of detention for most of the past 18 years. The military government has restricted her movements and those of her National League for Democracy Party - since it won elections in 1990 by a landslide but was never allowed to assume power.
The Bush administration has stepped up criticism of the Burmese government for its latest crackdown on dissent. Burma has arrested dozens of people who participated in rare protests against recent sharp hikes in fuel prices.
On Tuesday, the State Department rejected the outline for a new Burmese constitution as a sham. US officials say the 14-year process is not legitimate because the national convention was made up of delegates hand-picked by the country's military rulers.