Russian Foreign Minister Sergei Lavrov on Tuesday told an ally of Libya's eastern commander Khalifa Haftar that Moscow backed an immediate ceasefire and political talks that would culminate in united governing authorities.

Lavrov conveyed that message to Aguila Saleh Issa, speaker of the Libyan House of Representatives, in a phone call, Russia's Foreign Ministry said in a statement.

Issa is aligned to General Khalifa Haftar who controls the east of the country which opposes the internationally recognised Government of National Accord (GNA) in Tripoli.

The U.S. military earlier on Tuesday accused Russia of deploying fighter aircraft to Libya to support Russian mercenaries fighting for eastern forces, adding to concerns of a new escalation in the conflict.

There was no immediate response from the Russian Defence Ministry to a request for comment.