Ibrahim Gambari says the government should avoid any actions that run counter to the spirit of national reconciliation.
He also called on the country's ruling military junta to release detained pro-democracy leader Aung San Suu Kyi and end its repression of political dissidents.
Gambari made the comments Friday at the end of a two-day visit to Cambodia.
Thursday, Burmese security forces sealed-off Maggin monastery in Rangoon, forcing two monks and six novices off the premises.
The monastery was raided at least four times following the September protests, and its abbot U Indaka has been arrested and detained at an unknown location.
The Maggin monastery also provided housing for AIDS patients who came to Rangoon seeking treatment, but they also have been relocated.
Amnesty International says several people have been detained in Burma this month despite assurances from the military rulers the arrests would stop. Gambari says any further arrests violate "the spirit of national reconciliation" between the government and the opposition.
Burma drew international outrage over its bloody crackdown of pro-democracy protesters in September. Fifteen people were killed and another 3,000 people detained.
Gambari is touring the Southeast Asia region to encourage Burma's neighbors to play a role in resolving the crisis.
Information for this story is provided by UN news.