"We hope for the best," Kyi Win said.
The fresh appeal came as Aung San Suu Kyi's case was set to dominate an meeting between Barack Obama, the US president, and Thein Sein, the Myanmar junta's prime minister, in Singapore at a regional economic summit on Sunday.
The encounter would be the first meeting between a US president and a Myanmar leader in 43 years.
Kurt Campbell, the US assistant secretary of state for East Asian and Pacific affairs was the most senior US official to visit Myanmar for a decade and a half ealier this month.
Clinton, left, met Asian leaders in Singapore ahead of the APEC summit [AFP]
Campbell held talks with Aung San Suu Kyi after the ruling junta allowed her to make a rare public appearance.
Hillary Clinton, the US secretary of state, called on Myanmar on Thursday to free the 64-year-old, who has been in jail or under house arrest for 14 of the last 20 years.
Speaking in Singapore ahead of a summit of Asia-Pacific leaders, Clinton said the US remained committed to democracy in Myanmar, but added "we are not setting or dictating any conditions."
She added that Asian nations should reach out to Myanmar which has been under military rule since 1962, and that China, in particular, had an important role to play as Myanmar's biggest ally and trading partner.
The ruling junta refused to recognise the landslide victory of her National League for Democracy in elections in 1990.
The extension of her house arrest effectively keeps her out of the running for elections promised by the ruling generals at some time in 2010.