THE UN secretary-general said he planned to lobby Burma's junta chief directly today for the release of pro-democracy leader Aung San Suu Kyi.

He has acknowledged that his high-profile mission will be "very difficult".

UN Secretary-General Ban Ki-moon arrived in Burma for meetings with leaders on the same day that Ms Suu Kyi's widely criticised trial resumes.

The UN chief's visit magnifies the international spotlight on the trial, which has been delayed for a month but is expected to wrap up quickly after a final defence witness takes the stand today.

If Mr Ban is allowed to meet with Ms Suu Kyi, he will be the first UN secretary-general to do so since her first period of detention started in 1989.

UN spokeswoman Michele Montas said earlier this week that Mr Ban will push to personally meet her.

The 64-year-old Nobel Peace Prize winner is charged with violating the terms of her house arrest when an uninvited American man swam secretly to her lakeside home and stayed for two days.

She has pleaded not guilty but faces five years in prison if convicted.

The trial has prompted an outpouring of outrage from world leaders, Hollywood celebrities, Nobel laureates and human rights groups who say the junta is using the bizarre incident as an excuse to keep Ms Suu Kyi behind bars through to elections scheduled for 2010.