Sudan has urged the African Union to move its July summit from Malawi to its Addis Ababa headquarters after the host nation's refusal to welcome President Omar al-Bashir, the foreign ministry said Thursday.

Sudan informed the pan-African bloc of its request on Wednesday after Malawi announced that Bashir "would not be welcome at this summit, upon a claimed adherence of Malawi to its obligations to the so-called 'International Criminal Court'," the ministry said in a statement.

An "exceptional" airlift of almost 12,000 South Sudanese ended with a final flight from Khartoum on Wednesday but thousands more continue to live in makeshift conditions while they, too, await transport to the South, officials said.

One hundred Southerners took the last chartered plane from Khartoum to South Sudan's capital Juba at 1000 GMT, said Jill Helke, chief of the International Organization for Migration (IOM) in Sudan.

An increasing number of ethnic South Sudanese are living in makeshift conditions in the Sudanese capital, hoping for transport to South Sudan, the U.N. refugee agency said Tuesday.

Estimates from community leaders say that up to 38,000 South Sudanese are now staying in so-called "departure points" around the capital Khartoum, said Philippa Candler, assistant representative for protection with the office of the U.N. High Commissioner for Refugees (UNHCR) in Sudan.

Peace talks to end weeks of fighting between Sudan and South Sudan were deadlocked Tuesday after failing to agree on where to set up a demilitarized zone along their contested border.

Sudan's state security agency on Monday blocked distribution of the country's largest-circulation newspaper, which has criticized talks between Sudan and South Sudan, the newspaper's boss said.

Al Intibaha, a hardline anti-South daily which supported South Sudan's separation last July, has been a regular critic of negotiations between the two countries.

The defense ministers of Sudan and South Sudan are set to meet in the Ethiopian capital on Monday to discuss border security, a South Sudanese official said.

"The extraordinary meeting... will discuss the establishment of the various mechanism, including the joint border verification and monitoring mechanism and the establishment of the safe border demilitarized zone," Juba's chief negotiator Pagan Amum told Agence France Presse on Saturday.

Sudan has expelled four foreign aid groups working in the country's east, a source at the government's Humanitarian Affairs Commission told Agence France Presse on Friday.

"HAC decided to expel four international NGOs working in eastern Sudan because they failed in their planned projects," said the source, asking not to be named.

A Sudanese court on Thursday threw out the case against a prominent journalist who said it was inappropriate for President Omar al-Bashir to call South Sudan's government an "insect".

Journalists and press freedom advocates said the case against Faisal Mohammed Salih was symptomatic of a worsening government attack on critical voices over the past year, as tensions with South Sudan escalated following the South's independence in July.

South Sudan offered a cautious welcome Wednesday to foe Sudan's pullout of troops from the contested border region of Abyei, a year after Khartoum's army stormed the area forcing thousands to flee.

"We welcome of course the move by the Republic of Sudan... it's a sign of peace," said Information Minister Barnaba Marial Benjamin.

A British aid worker kidnapped nearly three months ago in Sudan's conflict-plagued Darfur region has been freed, the U.N.'s World Food Program said on Wednesday.

"After 86 days in captivity in the South Darfur region of Sudan, British aid worker Patrick Noonan, who was working for the U.N. World Food Program, has been released," WFP said in a statement.