Ministers from the Tripoli-based government visited the eastern city of Benghazi on Thursday.
A humanitarian source involved in the relief effort said eastern authorities had barred foreign aid flowing to Derna through the internationally recognised Tripoli government, whose legitimacy the eastern administration rejects.
A source in the eastern administration denied this, saying it had not rejected aid being channelled via Tripoli.
Relief operations in Derna have been directed by Haftar's LNA, the military coalition that controls eastern Libya and was for years in open conflict with western factions.
Turkey, long the main supporter of the Tripoli government, rapidly sent an aid team to Derna through Benghazi, the LNA-controlled capital of eastern regions.
Persons:
Ahmed Elumami, Ayman al, DERNA, Elias al, Biltrees, Tim Eaton, Khalifa Haftar, FAULTLINES, Eaton, OCHA, Haftar's LNA, Haftar, Emma Farge, Angelo Amante, Tom Perry, Angus McDowall, Alexandra Hudson
Organizations:
Reuters, Chatham House, United Nations, Brigade
Locations:
Libya, Misrata, Tripoli, Benghazi, Zawiya, Derna, NATO, Chatham, Libya's, Turkey, Geneva, Rome, Beirut