A United Nations representative is to meet with Sri Lankan government officials for urgent talks as thousands of Tamils remain detained in camps four months after the end of the civil war.
UN head of political affairs Lynn Pascoe says he is very concerned about slow progress on letting the refugees return home and will also raise the issue of the treatment of UN staff in Sri Lanka, the BBC reports.
A spokesperson for the Children's Fund has had his visa revoked, and two local UN staff have been detained.
Mr Pascoe also referred to agreements made by the government when UN Secretary-General Ban Ki-moon visited in May, including ones on accountability for possible violation of human rights laws.
The Sri Lankan government is letting more people return home, but still detains many others.
It has also just rejected the idea of an investigation by the European Union into its rights record, saying the country does not have human rights issues.