Darfur - Sudan's government says it will invite new aid groups to work in Darfur and allow those still operating there to expand their activities.

The UN's head of humanitarian affairs welcomed the move.

Sudan expelled 13 foreign aid groups in March after the nternational Criminal Court issued an arrest warrant for Sudanese President Omar al-Bashir.

Meanwhile, the backer of a conference on Darfur says it may be cancelled because of opposition from Sudan.

The UN says that up to 300,000 people have died during the conflict in Darfur and 2.7 million driven from their homes.

Sudan had agreed last month to allow some aid back into Darfur following its expulsion of humanitarian groups.

On Thursday, the minister for humanitarian assistance, Haroun Lual Ruun, said Khartoum would invite new non-governmental organisations (NGOs) to Darfur.

He also said it would allow those UN agencies and NGOs remaining in the Sudanese region to "expand their existing operations".

But he also said that if trust was restored between the humanitarian community and Sudanese authorities, capacity lost after the expulsions could be recovered.

The conference on Darfur that could now be cancelled was to bring together some 400 people from Darfur's diverse ethnic groups in the Ethiopian capital, Addis Ababa.

Pro-government groups as well as those close to Darfuri rebels were included.

Mr Bashir is accused by ICC prosecutors of orchestrating atrocities against civilians in Darfur, where his government has been fighting rebels since 2003.

He has dismissed the ICC's charges as a "neo-colonialist plot".