United Nations special envoy Tomas Quintana met Thursday in Burma with leaders of ethnic opposition parties and former political prisoners, as he wrapped up a four-day tour of the country that included a private meeting with pro-democracy leader Aung San Suu Kyi.

Quintana, in a statement, said he welcomes several initiatives by the new, nominally civilian government to improve a human rights record that Western leaders have strongly criticized and the United States has called abysmal. He said he is encouraged “at a key moment in Burma's history” by the reform priorities of President Thein Sein, and by moves in parliament to allow official media to report on human rights debate in the legislative body.

But the envoy also noted what he called “serious and ongoing human rights concerns” — chief among them the continued detention of several thousand opposition figures and supporters jailed during four decades of military rule. He also cited “continuing allegations” of torture and other abuses during official interrogations, the use of prisoners as porters for the military, and the transfer of prisoners to remote areas where they are unable to receive family visits.

He described his meeting with Aung San Suu Kyi as fruitful and productive, and said he discussed a range of human rights issues with the Nobel laureate.

Quintana, who is charged with assessing human rights in the Southeast Asian nation, had not been permitted to meet Aung San Suu Kyi during previous visits, while she was serving a lengthy term under house arrest in Rangoon.

Quintana said Thursday he also met with leaders of several opposition parties, including the National Democratic Force and the Democratic Party, and held talks with ethnic Mon and Karen leaders. He said the former political prisoners described a lack of health care and poor food while detained.

Earlier this week, the envoy met with several top government officials in the administrative capital, Naypyitaw, including Foreign Minister Wunna Maung Lwin, Chief Justice Tun Tun Oo, and Defense Minister Hla Min. He also attended a regular session of the country's new parliament, sworn in earlier this year after more than four decades of military rule in Burma.