The UN-African Union mission in Darfur has said that Sudan has asked it to close its human rights office in the capital, Khartoum, as tensions rise over investigations into an alleged mass rape.

The mission's attempts to investigate charges that government troops raped 200 women and girls in the Darfur village of Tabit last month have angered Khartoum.

On Tuesday, Abdallah al-Azraq, a senior foreign ministry official, in an interview with Al Jazeera issued counter-accusations against UNAMID.

"There are some who are associated with UNAMID raped women and committed acts of lewdness in Darfur and the UN did not lift their immunity and prosecute them or even asked them to depart the country," said Azraq.

The shutdown request "is not an escalation on our part or a restriction because of the spreading of false allegations about a mass rape in Tabit, Darfur, but we are trying to return... UNAMID to its mandate," said Azraq.

UNAMID said it was "working to clarify" the situation with the government.

The UN mission was set up in 2007 to protect civilians and secure aid to Darfur, which has been wracked by conflict since 2003 when ethnic groups rebelled against the government.

The conflict in vast Darfur region of western Sudan has killed more than 300,000 people and displaced two million, the UN says.

President Omar al-Bashir is wanted by the International Criminal Court for alleged war crimes in the region.

Source: Al Jazeera and agencies