Attorney Nyan Win said he and fellow lawyer Kyi Win were approached by the U.S. Embassy to represent Kyaw Zaw Lwin, who has been in prison since being arrested Sept. 3 on arrival at Yangon airport.
"We have accepted the offer," said Nyan Win, adding that the Foreign Ministry needed to confirm their appointment.
U.S. Embassy spokesman Richard Mei said he was unable to comment.
Dissident groups reported Kyaw Zaw Lwin's disappearance, but his whereabouts were unknown until he was allowed a U.S. consular visit Sept. 20 at Myanmar's Insein Prison.
According to dissident groups, Kyaw Zaw Lwin is a resident of Maryland in the U.S.
Several days after the consular visit, the embassy said it had made a formal complaint to Myanmar's military government based on claims by Kyaw Zaw Lwin that he was mistreated in prison.
The London-based human rights group Amnesty International has said that "trusted sources" reported he had suffered torture that included beatings and kicking and that he was deprived of food for seven days.
Myanmar authorities accuse Kyaw Zaw Lwin of entering Myanmar to stir up protests by Buddhist monks, who earlier spearheaded pro-democracy demonstrations in 2007 that were brutally suppressed by the junta. State radio and television say he confessed to plotting with dissident groups outside the country, and accused him of links to several activists inside Myanmar who planned to set off bombs.
Kyaw Zaw Lwin's mother is serving a five-year jail term for political activities and his sister was sentenced to 65 years in prison for her role in the 2007 pro-democracy protests, activist groups and family members said.
Lawyers Nyan Win and Kyi Win led the legal team that defended Suu Kyi in a recent high-profile trial that resulted in an extension of her house arrest. She is currently serving an 18-month sentence after previously spending 14 of the past 20 years in detention.