Tomas Ojea Quintana, the U.N. special envoy for human rights in Myanmar, said the new government there had made steps needed to usher in a genuine transition to democracy.
"Yet, many serious human rights issues remain and they need to be addressed," he said at the end of a five-day mission to the country.
Myanmar touted last year's general elections, the first in nearly two decades, as a path toward civilian leadership. The election was considered a sham by the international community.
Human Rights Watch, in a joint report with the Karen Human Rights Group, accused the military in Myanmar of torturing, executing and using convicted prisoners as human shields.
Quintana said Myanmar had a historic opportunity to tackle meaningful reforms in the country. He said "disturbing" reports of torture, the detention of "a large number of prisoners of conscience" and other rights and political concerns are worrying, however.
He noted that he was able to meet with opposition leader Aung San Suu Kyi and other reformers held by the former ruling military junta.
"I welcome what seems to be an opening of space for different actors and parties to engage in the political process," he said in a statement. "At the same time, I note the strong need to enhance the capacity and functioning of this new institution and of its members."
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