Bangkok  - US Secretary of State Hillary Rodham Clinton arrived in Bangkok Tuesday for a bilateral meeting with Thai Prime Minister Abhisit Vejjajiva.

She is to fly on to Phuket Island, 600 kilometres south of Bangkok, on Wednesday to attend the ASEAN Security Forum (ARF) the following day.

The ARF, Asia's main annual security event, on Thursday gathers foreign ministers from the 10 member states of the Association of South-East Asian Nations (ASEAN) and their main Asian and non-Asian allies such as the United States, the European Union and Russia.

Clinton is scheduled to sign the Treaty of Amity and Cooperation in South-East Asia, a loose agreement on the terms of engagement in the region on Wednesday, a turnabout from the previous administration, which had refused to sign the treaty.

President Barack Obama has indicated a change in the US approach in Asia, attaching more importance to multilateral groupings such as ASEAN rather than pursuing former president George W Bush's bilateral diplomacy.

The EU is expected to join the treaty later this year.

Before Clinton's arrival, Abhisit denied a report in Sunday's edition of The Washington Post that there was a US secret prison for torturing terrorists in Thailand.

"It's an old story, and it is totally groundless as this government has never resorted to the use of violent means," Abhisit was quoted as saying.

The US newspaper's report about CIA interrogations of suspected terrorists in 2002 mentions secret prisons in Thailand.

Abhisit said the report would have no impact on his scheduled meeting with Clinton. (dpa)