
Thailand, as the Chair of the group, has circulated the letter to other members including Burma, asking for consensus on the move.
After all members agree, the pardon request on behalf of Asean would be sent to Burma's paramount leader Gen Than Shwe, he said.
Aung San Suu Kyi was sentenced to another 18 months under house arrest after an American John Yettaw swam across the Inya Lake to her resident-cum-prison in Rangoon in May.
The verdict raised international outrage and leaders of many countries condemned the decision which they regarded as a political motivation to keep her away from the planned 2010 general election.