NAYPYIDAW: UN Secretary General Ban Ki-moon held a second meeting with the head of Myanmar's junta as he pressed the regime to free Aung San Suu Kyi and allow him to see the pro-democracy leader.

The new talks in the capital Naypyidaw lasted about 25 minutes but there was no immediate confirmation on whether military supremo Than Shwe had agreed to let Ban visit the Nobel Peace laureate in prison, UN officials said.

Ban pushed the iron-fisted Than Shwe during their first meeting on Friday to release all political prisoners including Aung San Suu Kyi, who is on trial for breaching the terms of her house arrest and faces up to five years in jail.

The UN chief was due to fly to the commercial hub Yangon after the meeting and then visit areas affected by deadly Cyclone Nargis in 2008, with the afternoon left free for any possible meeting with the opposition icon.

Ban would also give an unprecedented public address to diplomatic missions, UN agencies, international and non-governmental organisations in Yangon before his departure on Saturday evening, officials said.

His visit had been considered diplomatically risky because of its timing during her trial, and rights groups warned that it would be considered a major failure unless he managed to win Aung San Suu Kyi's freedom.

The 64-year-old was transferred from house arrest to Yangon's notorious Insein prison in May to face trial after an American man swam uninvited to her lakeside house.

She has been in detention for most of the past two decades since the junta refused to recognise her party's victory in the country's last elections in 1990.

"I told him that I wanted to meet her in person. He told me that she is on trial but I told him this is my proposal, this is important and I am waiting for their consideration and reply," Ban said after Friday's encounter.

"I am leaving (Saturday), so logically speaking I am waiting for a reply before my departure," he added.

Ban said he had also sought the release of more than 2,000 political prisoners that the UN says are held in Myanmar -- including Aung San Suu Kyi -- ahead of elections promised by the ruling generals for 2010.

Myanmar's tightly controlled state television showed footage of Ban meeting Than Shwe, who was wearing his olive green military uniform, and with representatives from political parties and ethnic groups.

UN officials travelling with Ban later said there had been a "very lively exchange of views" after Ban proposed a five-point agenda for reforms.

There was "considerable resistance" to the proposals, including the establishment of a UN "good offices" bureau in Yangon to provide a permanent structure for Ban and his special UN envoy to Myanmar, Ibrahim Gambari.

Aung San Suu Kyi appeared in court in Yangon on Friday but the trial was adjourned for a week because the judges had not received an earlier judgement barring two defence witnesses, her National League for Democracy said.

Critics have accused the junta of using the trial to keep her locked up for the elections, although Ban said that Than Shwe assured him that the elections would be held in a "fair, free and transparent manner."

The case has sparked international outrage, with US President Barack Obama calling it a "show trial" and a host of world leaders and celebrities calling for her release.

Ban has faced recent criticism for his softly-softly approach to the job of secretary general, but diplomats say he hopes his quiet brand of diplomacy will pay dividends with Myanmar's generals.

The visit is Ban's first to Myanmar since he persuaded the junta to accept international aid following Cyclone Nargis in May 2008, which killed around 138,000 people.

Myanmar, formerly known as Burma, has been ruled by the military since 1962.