Mr Gambari met detained opposition leader Aung San Suu Kyi in Rangoon on Sunday, but has yet to meet the country's senior generals.
Heavily-armed troops and police remain on the streets of Rangoon to prevent new pro-democracy protests.
Mr Gambari is hoping to end a crackdown on anti-government protesters.
On Sunday, he met some of the country's military leaders in the new capital Naypyidaw, and has now returned there for further talks.
But he did not meet senior general Than Shwe, or his deputy Maung Aye.
Monks detained
Mr Gambari is believed to be the first foreigner to meet Ms Suu Kyi for 10 months.
Her National League for Democracy won a landslide victory in elections in 1990, but the results were annulled by the junta.
Mr Gambari earlier met Burma's acting prime minister, deputy foreign minister and ministers of information and culture.
Burma has seen almost two weeks of sustained popular unrest.
But the number of protesters on the streets is now much smaller than at the height of the rallies, and the Buddhist monks who led the initial protests are now being prevented from leaving their monasteries.
However, a correspondent in Rangoon - who must remain anonymous for her own safety - said people were too scared to do anything with so many military around.
She says people told her they felt afraid and helpless, having seen that the military is prepared to shoot monks, women and children.
But, she added, people assured her that the demonstrations would continue.
UK Ambassador Mark Canning told the BBC there were around 15,000 troops in Rangoon, and there had been no reports of further protests there on Sunday.
"They've managed to stamp a picture of normality, but only with a heavy military presence," he said.
Rare criticism
The government says 10 people were killed last week in the suppression of the opposition protests.
Diplomats and activists say the number killed was many times higher.
The country's leadership usually ignores outside pressure.
But the crackdown has prompted rare criticism from China and the Association of South East Asian Nations (Asean), of which Burma is a member.
A Japanese envoy is also due to arrive in the country, to ensure a full investigation into the death of Japanese video journalist Kenji Nagai.
Footage of his death last Wednesday appears to show a soldier shooting him at close range as security forces cleared central Rangoon of protesters.
