Libya has told the United Nations that aid workers will be given access to areas under government control.
UN officials say an agreement has been reached for humanitarian personnel to set up in the capital, Tripoli, and operate elsewhere.
In the latest fighting meanwhile, pro-Gaddafi forces are reported to have resumed their bombardment of the western city of Misrata.
And state television said there had been more air strikes by NATO on Tripoli and in Sirte, east of the capital.
Meanwhile, the World Food Programme said it had started moving supplies through a new humanitarian corridor into western Libya, with the first convoy crossing from Tunisia on Monday.
It was loaded with enough wheat flour and high-energy biscuits to feed 50,000 people for 30 days.
The BBC reports the food will be delivered to several cities, although not Misrata.