Washington - US President George W Bush left late Monday for Asia on a seven-day trip to South Korea, Thailand - where he is to deliver a major policy speech and meet with Myanmar dissidents - and China for the opening ceremonies of the Beijing Olympics.

Bush was to arrive late Tuesday in Seoul, where he will meet Wednesday with President Lee Myung Bak, who visited the US in March at the presidential retreat at Camp David, Maryland. The two leaders will mark the 55th anniversary of US-South Korean ties.

Bush will arrive late Wednesday in Bangkok for his second visit to the Thailand, where he plans to meet with Prime Minister Samak Sundaravej. The two leaders will mark the 175th anniversary of bilateral ties between their countries.

The US president is to arrive Thursday in China and will attend the opening ceremonies of the Summer Games on Friday in Beijing. During his China stay through Monday, Bush plans to meet with Chinese President Hu Jintao, Premier Wen Jiabao and Vice President Xi Jinping.

Over the objections of political critics in the US, Bush has said he regards his attendance at the Olympics as a purely a "sporting event."

Bush met last week with Chinese dissidents, and the US House of Representatives passed a resolution urging the Beijing government to protect human rights and withdraw support from the governments of Myanmar and Sudan to protest human-rights abuses in those two countries.

During his stay in Thailand, Bush plans to highlight the kingdom's role as a major non-NATO ally of the US and "one of our best relationships in East Asia," Dennis Wilder, a top official in the National Security Council, said last week.

"The president will congratulate the Thai people on the return to democracy in Thailand," Wilder said.

Bush's major address in Thailand will be on US policy in Asia and will look back on the Asia-related accomplishments of his nearly eight years in office. He will visit the Mercy Centre, an HIV/AIDS facility for children, White House officials said.

Myanmar's political situation will be on the agenda, with Bush planning to have lunch with Myanmar democracy activists and to offer broadcast interviews with the press in Thailand that are to be beamed into Myanmar.

First Lady Laura Bush plans to visit the Mae La refugee camp on the Thai-Myanmar border. She has been actively promoting human rights in Myanmar and protesting abuses that followed demonstrations by Buddhist monks earlier this year, and the Myanmar regime's initial blockade of foreign relief workers trying to help survivors after the devastating Cyclone Nargis in May.

In South Korea, Bush was expected to thank the government for reopening its markets to US bone-in beef for the first time in five years. Seoul had banned the imports after the US reported a few cases of "mad-cow" disease in cattle. (dpa)