In a statement marking Aung San Suu Kyi's birthday, the US secretary of state rebuked the military for continuing her detention, which she said was a violation of the democracy leader's fundamental rights.
"This deplorable situation must end," Condoleezza Rice said in Washington, noting that Myanmar's generals were holding nearly 2,000 others as political prisoners.
Aung San Suu Kyi has been held in jail or under house arrest for almost 13 of the last 18 years, since the military annulled the victory or her National League for Democracy in national elections held in 1990.
On Thursday morning Myint Soe, an NLD member who buys and brings daily food for Aung San Suu Kyi, offered 64 roses at the Shwedagon pagoda and laid an equal number of yellow chrysanthemums at her mother's tomb at the foot of the temple, party sources said.
Dozens of people gathered outside the NLD headquarters offering meals to Buddhist monks amid tight security around the area.
"Later, we will release nine doves to bring peace and freedom to Daw Suu Kyi," said Lai Lai, one of the party members.
There were reports of plainclothes security personnel and additional barricades put up around the party headquarters and near Aung San Suu Kyi's home.
On Wednesday Jared Genser, Aung San Suu Kyi's US lawyer, filed a petition with the UN Working Group on Arbitrary Detention saying her extended detention was illegal under Myanmar laws.
The country's State Protection Law says that a person can be held without charge or trial for only up to five years, renewable for up to one year at a time.