The UN has appointed a new envoy on Libya and is to send a humanitarian team as the battle between forces loyal to Col Gaddafi and rebels intensifies.

UN chief Ban Ki-moon named a former Jordanian minister to deal with Libya and said Col Gaddafi agreed to allow an assessment team into Tripoli.

The UN's top humanitarian official also demanded urgent access to the town of Misrata after fierce fighting there.

Rebels have been trying to fight off a counter-offensive by Gaddafi forces, who have been attacking both near Tripoli and in the east after recent rebel gains.

A statement from Mr Ban's office said the UN secretary general "notes that civilians are bearing the brunt of the violence, and calls for an immediate halt to the government's disproportionate use of force and indiscriminate attacks on civilian targets".

The statement continued: "He stresses that those who violate international humanitarian law or commit grave crimes must be held accountable."

Mr Ban has appointed Jordan's former foreign minister, Abdelilah Al-Khatib, as his special envoy "to undertake urgent consultations with the authorities in Tripoli and in the region on the immediate humanitarian situation," the statement said, BBC reports.