A two-member United Nations security team has met Islamist leaders in the Somali capital, Mogadishu.
The Islamists control much of southern Somalia
It is the UN's first contact with Mogadishu's new rulers since they took over from the warlords a month ago.
Islamist fighters are trying to disarm Abdi Awale Qeydiid, the last of the warlords they defeated in Mogadishu, some 30km from the city.
Earlier another warlord, Omar Finish, surrendered, with some 100 fighters and nine armed pick-up trucks.
The warlords are widely believed to have been backed by the US, which is worried about the Islamist advances in Somalia, fearing they could be linked to al-Qaeda.
Somalis, weary after 15 years without an effective national government, are worried about a possible new conflict between Islamist and secular forces in their country.
'No al-Qaeda links'
Chief UN chief security adviser for Somalia Joe Gordon met one of the Islamist leaders, Sheikh Sharif Sheikh Ahmed, and toured several parts of the city, including the port and airport, under heavy security.
"The team wants to check security in the capital before UN agencies can resume their work here," Abdirahim Isse, a close aide to Mr Ahmed, told Reuters news agency.
Most aid workers have pulled out of Mogadishu because it is too dangerous. A Swedish journalist was shot dead at a rally in the city last month.
Meanwhile, another Islamist leader, Sheikh Hassan Dahir Aweys, has said that a statement attributed to Osama bin Laden had "nothing to do with" the Union of Islamic Courts.
The prime minister of the weak interim government has told Bin Laden not to interfere in Somalia following an internet audio recording attributed to the al-Qaeda leader, warning the west not to send troops to Somalia.
'Enemy number one'
Regional diplomats are heading for Somalia on Monday for talks with the government in their base of Baidoa, 200km form Mogadishu.
It was not clear whether the team from East Africa's Igad body and the African Union will also travel to Mogadishu for talks with the Union of Islamic Courts, which controls much of southern Somalia.
On Sunday, Mr Ahmed pointedly said that any foreigners planning on going to the capital would need the Islamists' approval.
Igad has agreed to send peacekeeping troops to Somalia - but only when it is safe to do so.
The government of President Abdullahi Yusuf wants foreign peacekeepers to be deployed - an idea fiercely rejected by the Union of Islamic Courts.
At a summit in The Gambia, African Union leaders agreed to support Somali's government.
Mr Ahmed dismissed having any links to al-Qaeda and again said that Ethiopian troops had already been sent to Somalia and were in the government's seat of Baidoa, 200km from Mogadishu.
He urged Somalis to unite against "the enemy number one of the Somali people", apparently referring to Ethiopia.
Prime Minister Ghedi, however, again strongly denied the claims - as Ethiopia has done in the past.
Mr Ghedi also urged any foreign militants in Somalia to leave the country.
Mr Finish was religious affairs ministers in the government until he was sacked for his role in the Mogadishu battle.
He has promised to set up a new Islamic court in the Madina district he used to control.