NAYPYIDAW, Myanmar – Myanmar junta supremo Than Shwe smiled briefly but gave nothing away as he listened Friday to U.N. chief Ban Ki-moon, at the start of what Ban has called a tough mission to promote democratic reform.

I thank you for your invitation. I'm happy to be here and to see you are in good health since I last saw you, Ban told the 76-year-old general, wearing a khaki uniform adorned with medals.

The rare meeting with the reclusive general took place in Than Shwe's lavish Bayint Nuang Yeiktha office in Naypyidaw, the new capital hastily built in the hills of Shan Plateau in 2005.

Ban, on what he has called a tough mission to press the junta to release all political prisoners and hold fair and credible elections, commended the general for his contributions to peace, prosperity and democracy in the former Burma.

I would like to help move your country forward and appreciate your commitment to moving your country forward, Ban said, offering a smile and a firm handshake to the man who has led the military regime for 17 of its 47 years in power.

Moments later, the media were ushered out of the room. Ban was expected to ask Than Shwe's permission to meet opposition leader Aung san Suu Kyi, who is on trial for breaching the terms of her house arrest.

Suu Kyi's trial was adjourned earlier Friday because of a clerical error by the court, according to her lawyer.

On arrival in Yangon, Ban said he would convey international concern about Suu Kyi's trial and press the regime to ensure next year's multi-party elections are credible and transparent.

The genuine will of the Myanmar people should be reflected.

HIGH STAKES

The stakes are high for Ban and the risk of failure great.

Halfway through a five-year term at the helm of the United Nations, he has faced a wave of criticism from detractors who say his low-key approach to the job does not work. He is eager to prove them wrong, U.N. diplomats say.

Ban made clear he was under no illusions about how difficult it would be to persuade the military junta to free prisoners and take concrete steps toward democracy ahead of the elections.

I'll do my best (but) I do not believe my visit should be a make-or-break event... This will be a very difficult mission, he told reporters in Singapore earlier Friday.

He said he would also press Than Shwe and Prime Minister Thein Sein to engage in meaningful and credible dialogue with Suu Kyi and the opposition.

Ban said he would meet with representatives of registered political parties in Naypyidaw, including Suu Kyi's National League for Democracy.

However, Suu Kyi herself will not be at that meeting and it was not clear if Ban would be able to meet her at all.

She has spent 14 of the past 20 years in detention, mostly under house arrest at her lakeside home in Yangon. It will be up to Than Shwe whether Ban sees her.

Her lawyer said her trial had been postponed until July 10, apparently because the Supreme Court did not send case files to the district court, where Suu Kyi appeared Friday.

Daw Aung San Suu Kyi expressed her surprise that this happened, lawyer Nyan Win told reporters.

The Nobel laureate, 64, was charged with violating the terms of her house arrest by allowing an American intruder to stay at her home in May, which prosecutors say breached a security law designed to thwart subversive elements.

Critics say the charges are trumped up and that the trial is an attempt to keep Suu Kyi out of the way for the elections, expected to entrench nearly half a century of army rule.

Ban had expressed concern his visit would be used by the junta for propaganda purposes but he decided to go anyway, hoping his knack for quiet diplomacy would persuade the generals to compromise, as they did last year when Ban convinced them to lift humanitarian aid restrictions after Cyclone Nargis.

Analysts say Ban may have been given some indication by the generals, or by U.N. envoy Ibrahim Gambari after his trip last week, that his visit might bring some kind of positive result.

Human Rights Watch said Ban should not accept the return of opposition leader Aung San Suu Kyi to house arrest or vague statements about political reform as signs of a successful visit.

(Writing by Martin Petty; Editing by Alan Raybould)

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