Human Rights Watch says Burma's indefinite extension of the detention of a prominent opposition party leader highlights the country's lack of commitment to political change.
The Asia director at the New York based human rights group, Brad Adams, said the move shows how Burma's military is fearful of political dissidents striving for democracy.
On Tuesday, Burmese authorities extended the house arrest of the deputy leader of the National League for Democracy, U Tin Oo. The party overwhelmingly won the 1990 general election but the military government barred it from taking power.
Tin Oo was arrested along with party leader Aung San Suu Kyi in 2003.
Human Rights Watch says the Burmese government holds more than one thousand known political prisoners in prisons and labor camps across the country.