Yangon  - A Myanmar court postponed the controversial trial of opposition leader Aung San Suu Kyi on Friday, minutes after the arrival of United Nations Secretary-General Ban Ki-moon to the military-run country.

"The trial has been postponed until July 10," Nyan Win, one of Suu Kyi's lawyers, said.

On Friday defence witness Khin Moe Moe was scheduled to testify at a court set up at Insein Prison to try Suu Kyi for breaking the terms of her detention by allegedly permitting US national John William Yettaw to swim to her lakeside home-cum-prison on May 3 and stay until May 5.

"Insein Prison court judges said they were still awaiting case documents from the Supreme Court so they decided to postpone Khin Moe Moe's testimony," Nyan Win said.

The postponement was announced minutes after UN chief Ban arrived in Yangon on a two-day official trip designed to press Myanmar's ruling junta to release Suu Kyi, the leader of the National League for Democracy opposition party, and some 2,100 other political prisoners in the military-ruled nation.

Ban was scheduled to travel to Naypyitaw, 350 kilometres north of Yangon, to meet with military supremo Senior General Than Shwe, and representatives of the NLD, other political parties and ethnic minority groups.

Ban is expected to urge Than Shwe to release Suu Kyi, but Myanmar watchers doubt he will succeed in persuading the general. It is still unclear whether he will be allowed to meet with Suu Kyi, who is now a resident of Insein Prison.

Suu Kyi's trial began May 11. While the prosecution was allowed to present 14 witnesses in the first week, the defence was initially allowed only one. Later a second witness, NLD member and attorney Khin Moe Moe, was permitted.

Suu Kyi, who has spent 13 of the past 19 years in detention, stands accused of breaking the terms of her latest house detention by permitting Yettaw, a 53-year-old Vietnam War veteran and member of the Mormon sect, to swim to her house on Yangon's Inya Lake May
3 and spend two nights there before swimming away.

Critics have accused the military junta of using the case as a pretext to keep the 1991 Nobel Peace Prize laureate in jail during a politically sensitive period leading up to a general election planned for next year.

Suu Kyi's NLD won the 1990 general election by a landslide but has been blocked from power by Myanmar's junta for the past 19 years.

The new trial of Suu Kyi, whose most recent six-year house detention sentence expired May 27, has sparked a chorus of protests from world leaders and even statements of concern from its regional allies in the Association of South-East Asian Nations. (dpa)