US Secretary of State Condoleezza Rice has called on Thailand and other nations in South East Asia to press for change in neighbouring Burma.
Condoleezza Rice was welcomed by Prime Minister Thaksin Shinawatra
She was speaking while on a visit to Thailand as part of a regional tour.
A BBC correspondent says Washington and Bangkok have had opposite approaches to Burma: Thailand engages, while the US isolates the junta in Rangoon.
Ms Rice also expressed confidence in Thai efforts to tackle the violence in the mainly Muslim south of the country.
She welcomed the appointment of a reconciliation committee, saying it was typical of the way in which democratic states handled difficult situations.
Her comments came in a press conference after talks with the Thai Prime Minister Thaksin Shinawatra and Foreign Minister Kantathi Suphamongkhon.
She described Aung San Suu Kyi, Burma's pro-democracy leader under house arrest in Rangoon, as "someone who represents the possibility of reconciliation" for Burma.
"I have asked that our Thai friends who have relations with Burma and dialogue with Burma to continue to press the case of those who are held, including Aung San Suu Kyi, and to press the Burmese toward a more open society," she said.
Mr Suphamongkhon told the press conference that Thailand, too, wanted to see reforms in Burma.
"We do want to see democracy and the national reconciliation process completed in Burma as soon as possible," he said.
Ms Rice avoided any comment on the prospect of Burma taking on the chairmanship of the 10-member Association of South-East Asian nations (Asean) later this year.
But she did apologise for missing an important Asean meeting in Laos later this month, saying she had a schedule conflict.
Thailand had feared a diplomatic snub, but Ms Rice was all charm, says the BBC's Kylie Morris in the resort island of Phuket where the talks took place.
Ms Rice described Phuket, which was badly hit by December's tsunami, as a beautiful paradise.
And she congratulated Thailand on the way it dealt with the tsunami's aftermath.
Our correspondent says it is no accident that the talks were held in Phuket; Ms Rice was keen to highlight the role played by the US in reconstruction after the tsunami.
She was due to visit a school and survey rehabilitation in the worst-hit province of Phang Nga.
Thai foreign ministry officials have said they are keen for Washington to develop the positive image it won in the region after the tsunami, and remain strongly engaged there.