In a strongly worded statement released late on Tuesday in New York, Mr Annan called for the military junta to engage Ms Suu Kyi's National League for Democracy in "substantive dialogue" on the nation's future.
The ongoing national convention, which aims to draft a constitution and pave the way for elections, does not "adhere to the recommendations made by successive resolutions of the [UN] general assembly", he said.
Mr Annan crucially hinted that, for the first time, Burma's neighbours are starting to lose patience with the military regime, which has been in power for four decades.
No one from the SPDC was willing to comment on the statement yesterday.
Activist groups applauded Mr Annan's statement but said it was unclear what the UN chief would do if the generals declined to cooperate.
