Former Jordanian foreign minister Abdelilah Al-Khatib will undertake "urgent consultations" with Kadhafi's government on the growing battle with rebel forces and work on the humanitarian crisis it has caused, UN spokesman Martin Nesirky said.
The United Nations has demanded "urgent" access to the rebel-held Libyan city of Misrata, which has come under attack from regime forces, and the UN secretary general has expressed growing concern over what he has called Kadhafi's "disproportionate" use of force.
Ban "strongly appealed for an end to the hostilities" in telephone talks with Libya's Foreign Minister Mussa Kussa, Nesirky said.
Ban called on Kadhafi's government "to ensure the safety of all foreign nationals and unhindered access for humanitarian organisations to people in need.
"In this regard, he suggested the immediate dispatch of a humanitarian assessment team to Tripoli, a request that was agreed to by the foreign minister," Nesirky said.
The team is being organised by the UN Office for the Coordination of Humanitarian Affairs which has had experts in the eastern rebel capital of Benghazi.
It was not immediately known where the team would be allowed to go in Tripoli, and whether they would be taken to other cities.
Ban spoke with Kadhafi on February 21 but was unable to convince the Libyan leader to halt his crackdown on opposition protests which rights groups say has now left several thousand dead. The UN Security Council ordered sanctions against Kadhafi five days later.
The UN said that the former Jordanian foreign minister would come to New York this week before taking up his responsibilities in the region.