New York  - Sudan said Thursday it will not allow the 13 humanitarian organizations expelled from the troubled Darfur region to resume their work there.

"It is not reversible because we did it for our national interests," Sudan's UN Ambassador Abdalmahmood Mohamad told reporters while the UN Security Council was holding a closed-door discussion on the situation in Darfur.

Mohamad criticized the 15-nation council, which is under Libyan presidency in March, for the off-limits debate despite requests by some delegations for an open session to hear a briefing on Darfur from Djibril Bassole, the UN-African Union mediator in the conflict.

Oxfam, CARE and Doctors Without Borders are among the 13 groups for which Khartoum cancelled work permits and expelled in retaliation for the decision by the International Criminal Court (ICC) to seek the arrest of President Omar al-Bashir for crimes against humanity and war crimes in Darfur.

The groups expelled were responsible for half of the humanitarian assistance given to hundreds of thousands of Darfurians.

The council has put pressure on Khartoum to reverse its decision and return the relief groups. But Mohamad made it clear that the government sees the decision as irreversible. (dpa)