Members of Libya's UN-backed Presidential Council have arrived in the capital, Tripoli, a Reuters reporter said.

Seven members, including Fayez Seraj, the head of the council and prime minister of Libya's unity government, arrived at Tripoli's naval base after travelling by boat from Tunisia.

Tripoli's self-declared government and armed groups that back it had in recent days warned the unity government not to travel to the Libyan capital.