The United States on Thursday called for the immediate withdrawal of Russian and Turkish forces from Libya, after a deadline for them to leave was ignored.

This appeal marked a firmer expression of US policy toward oil-rich Libya under the new administration of President Joe Biden.

"We call on all external parties, to include Russia, Turkey and the UAE, to respect Libyan sovereignty and immediately cease all military intervention in Libya," the acting US ambassador Richard Mills said during a UN Security Council meeting on Libya, which has seen a decade of fighting since the overthrow of Moamer Kadhafi.

Under a UN-backed ceasefire signed October 23, foreign troops and mercenaries were to pull out of Libya within three months. That deadline passed on Saturday with no movement announced or observed on the ground.

"Per the October ceasefire agreement we call on Turkey and Russia to immediately initiate the withdrawal of their forces from the country and the removal of the foreign mercenaries and military proxies that they have recruited, financed, deployed and supported in Libya," said Mills.

The UN estimates there are some 20,000 foreign troops and mercenaries in Libya helping the warring factions: the UN-recognized Government of National Accord in Tripoli and military strongman Khalifa Haftar in the east.

According to the UN, Haftar has the backing of the United Arab Emirates, Egypt and Russia, particularly mercenaries from a private group with links to Vladimir Putin. The GNA is supported by Turkey and Syrian rebels transferred to Libya.

Mercenaries in Libya include several thousand each from Syria and Sudan and a thousand from Chad, a diplomat said on condition of anonymity.

The statement by Mills signaled a clearer tone in US policy under Biden. While in power, his predecessor Donald Trump at one point seemed to back Haftar, although the official US policy at the end of his administration was that all foreign fighters should leave in line with the UN-backed agreement.

Fighters fire salutatory rounds in the air during a funeral for a commander of the Special Forces of the self-proclaimed Libyan National Army loyal to strongman Khalifa Haftar, in the eastern city of Benghazi on November 1, 2020
Fighters fire salutatory rounds in the air during a funeral for a commander of the Special Forces of the self-proclaimed Libyan National Army loyal to strongman Khalifa Haftar, in the eastern city of Benghazi on November 1, 2020 AFP / Abdullah DOMA

Russia denies having any military personnel in Libya.

"We don't have any military personnel or servicemen on Libyan soil. Therefore there is no Russian military intervention in Libya," a spokesperson for the country's mission told AFP.

"If there are any Russian nationals as mercenaries, which we cannot totally exclude, those who hired them should be addressed to withdraw them."

At Thursday's council meeting, most members also called for the withdrawal of foreign forces from Libya and respect for an arms embargo in force since 2011.

Russian ambassador Vassily Nebenzia in his remarks to the council made no mention of the presence of foreign fighters.

UN Secretary-General Antonio Guterres also called for the departure of the fighters.

"It's essential that all foreign troops and all foreign mercenaries move first to Benghazi and to Tripoli and, from there, move back and leave the Libyans alone, because the Libyans have already proven that, left alone, they are able to address their problems," he said.

In a declaration adopted unanimously Thursday by the 15 Security Council members -- including Russia -- the panel "called for the withdrawal of all foreign fighters and mercenaries from Libya without further delay."

The UN says the arms embargo is being violated as cargo planes arrive with weapons for the two warring sides.

"This blatant foreign interference continues," said acting UN envoy Stephanie Williams, while noting that a ceasefire was still in place.

UN-sponsored talks among the two sides in Libya are expected to resume in the near future in Geneva. Libya is scheduled to hold elections in December.