U.N. officials gave no details of Gambari's 50 minutes with the Nobel laureate, who was taken from the state guest house where they met back to the lakeside Yangon villa where she has been under house arrest since May 2003.

An Information Ministry source said Gambari met Information Minister Kyaw Hsan, the highest-ranking official he met during his trip, after talks with Suu Kyi.

The Nigerian diplomat then left the former Burma for Singapore, ending his third visit since September's brutally crushed pro-democracy marches.

Gambari appeared to get nowhere with his efforts to convince the junta to include Suu Kyi and her National League for Democracy (NLD) in its plans for political reforms in a seven-step "roadmap to democracy".

In singularly blunt language, state media said the generals would consider no changes to their roadmap and spurned his offer of observers for May's constitutional referendum and elections in 2010, redoubling concerns about the freedom and fairness of both polls.

They also said they had no need for external expertise in running the elections, saying they had "enough experience".

The last time they allowed elections, in 1990, they were forced to ignore the result when Suu Kyi's party won more than 80 percent of the vote.

The crackdown against last September's protests sparked worldwide outrage and a major diplomatic push for political reform in the former British colony, which has been under military rule since 1962.

However, with veto-wielding U.N. Security Council members China and Russia unwilling to see the imposition of binding international sanctions, the generals have refused to budge from a roadmap that the West derides as a sham.