Yangon - Myanmar's human rights situation remains "challenging," United Nations Special Human Rights Envoy Rapporteur Tomas Ojea Quintana concluded Thursday, winding up a six-day visit to the junta-ruled nation.

The junta refused to allow Quintana to meet with either Aung San Suu Kyi, the longstanding leader of the opposition, or Myanmar's junta chief Senior General Than Shwe during the trip.

"The human rights situation in Myanmar is still challenging," Quintana said shortly before departing the country late Thursday night.

Quintana arrived on Saturday on a mission to push for the freedom of an estimated 2,100 political prisoners, including Suu Kyi who has spent 13 of the past 19 years under house arrest, and to assess abuses against ethnic minority groups opposed to the regime.

The UN human rights envoy travelled to the junta's headquarters in Naypyitaw Wednesday where he met with Myanmar's interior minister to push for the freedom of political prisoners.

"He said he will consider my recommendations," Quintana told a press conference.

Quintana also met with Myanmar's chief justice and attorney general, who said they would consider amending some national laws to be more in keeping with international standards, although he received no firm commitments.

Than Shwe has refused meetings with any UN representatives since May, when he granted an audience with UN Secretary General Ban Ki-moon.

While in Myanmar, the UN rapporteur on human rights also visited jails in the Karen State, home to some of the country's most prolonged unrest, and the notorious Insein prison in Yangon, meeting with several political prisoners.

On the eve of Quintana's arrival in Yangon Saturday, Myanmar authorities sentenced Tin Oo, the 82-year-old deputy leader of the opposition National League for Democracy (NLD), to another year under house arrest.

Critics of the UN visit called it a "showboat" mission for the junta, permitting it to improve its image at the 14th summit of the Association of South-East Asian Nations in Thailand later this month.

While allowing the visit, the regime sent a clear message to Quintana that it will continue to brook no domsestic political opposition.

Besides slapping another year on to Tin Oo's house arrest Friday, the day before Quintana's arrival, Myanmar courts sentenced NLD members Nyi Bu and Tin Min Htut to
15 years for sending an open letter to the UN in August that was critical of the military's plans to set up a civilian government.

Quintana hopes to persuade the junta to free hundreds of political prisoners before a scheduled general election in 2010.

His mission was to encourage the regime to progressively release "prisoners of conscience," giving independence to the judiciary, bringing laws into line with international human rights standards and training officials to respect these rights, according to a statement released by the UN in Geneva. (dpa)