Officials in Libya's UN-recognised government say they plan to confront Moscow over the alleged deployment of Russian mercenaries to fight alongside their opponents in the country's civil war.
Libyan and US officials accused Russia of deploying fighters through a private security contractor, the Wagner Group, to key battleground areas in Libya in recent months.
They say the Russian fighters are backing renegade military commander Khalifa Haftar, whose forces have been trying for months to capture the capital, Tripoli, where the UN-recognised Government of National Accord is based.
The GNA has documented between 600 and 800 Russian mercenaries in Libya and is collecting their names on a list to present to the Russian government, according to Khaled al-Meshri, head of the GNA's Supreme Council of State.
"We are going to visit Russia after we collect all evidence and present to the authorities and see what they say," al-Meshri told The Associated Press last week.
He did not say when the visit would take place. Moscow has repeatedly denied playing any role in Libya's war.
Allegations of Russian intervention
Haftar's Libyan National Army - made up of army units, ultra-conservative militias, and tribesmen - launched its offensive on Tripoli in April after seizing much of eastern Libya from rivals in recent years.
Haftar is backed by the United Arab Emirates and Egypt, as well as France and Russia, while the GNA receives aid from Turkey, Qatar and Italy.
Libya was plunged into chaos when a NATO-backed uprising toppled longtime ruler Muammar Gaddafi in 2011. The country is now split between a government in the east, allied with Haftar, and the GNA in Tripoli in the west. Both sides are bolstered by militias.
Fighting has stalled in recent weeks with both sides dug in and shelling one another along Tripoli's southern reaches.
David Schenker, US assistant secretary of state for near east affairs, told reporters last week the State Department is working with European partners to impose sanctions on the Russian military contractor responsible for sending fighters to Tripoli.
"The way that this organization of Russians, in particular, has operated before raises the spectre of large-scale casualties in civilian populations," he said.
Schenker's comments came shortly after US officials met with Haftar to press for a ceasefire and "expressed serious concern" over Russia's intervention in the conflict.
But US President Donald Trump has sent decidedly mixed messages to Haftar.
Trump voiced support of Haftar when he launched his attempt to take over Tripoli, praising the commander's "anti-terrorism" efforts in a phone conversation. The call was a sharp break with the US policy of supporting Libya's Tripoli-based Prime Minister Fayez al-Sarraj.
Haftar's offensive dealt a blow to UN efforts to bring the warring parties together. Al-Meshri called for confidence-building measures and a push towards presidential and parliamentary elections.
"Since Gaddafi's ouster, there have been no presidential elections. People are fed up," he said.
'Not positively engaged'
Al-Meshri maintained his administration has strong evidence there are Russians fighters on the ground.
He said government forces found mobile phones, intercepted communications, and seized personal belongings left behind in the chaos of battle.
He said flight data show dates and names of Russians moving from Syria to Egypt and then the Jordanian capital of Amman before flying to the eastern Libyan city of Benghazi, Haftar's seat of power. He didn't elaborate or present any of these documents.
Wagner Group is believed to have sent mercenaries to multiple conflicts, including Syria, Ukraine, and elsewhere, raising accusations that Moscow is using the force to spread its influence.
The firm is a military contractor run by Yevgeny Prigozhin, a businessman with close ties to the Kremlin. Russian officials have refused in the past to comment on the company's activities.
The Russians' presence has further mired an already complex conflict.
By deploying fighters into Libya, Russia is embroiling itself in another conflict in the Middle East. Its military is involved in Syria's civil war, conducting air attacks and deploying troops and military police.
That operation successfully shored up Syrian President Bashar al-Assad's government and - at a relatively modest financial cost - helped Moscow expand its clout in the region.
Analysts said Russian President Vladimir Putin is trying to find leverage with Western powers in oil-rich Libya and recognises the country is a gateway for many migrants trying to reach European shores, they said.
"Most of this is smoke and mirrors designed to induce fear," said Anas Gamati, founder of the Tripoli-based Sadeq Institute.
"Russian influence has done only two things: inflate their size and spectre of their power in Libya. They're not positively engaged or trying to play a constructive role with diplomatic or political value."
Officially, Russia continues to maintain a dialogue with both sides. Haftar has visited Moscow several times the past few years and a delegation of the Tripoli-based government met with Putin during a Russia-Africa Economic Forum summit in Sochi in October.
'Music to Putin's ears'
The allegations of Russian interference come amid a renewed push for international players to reach a consensus on Libya.
Germany is working with the UN to host a conference on Libya by early 2020. Observers hope international players could exert enough pressure to stop the fighting.
"We don't want to go back to square one," Gamati said.
As long as international powers remain divided, Libya's conflict risks continuing to play out as the world's latest proxy war, some observers warned.
"Putin would like nothing more than to keep Europe busy and divided over Libya, scared of illegal immigration, paralysed by right-wing populism that threatens the very idea of the EU," said Mohammed Eljareh, an analyst who runs Libya Outlook, a consulting company on Libyan affairs.
"All of this is music to Putin's ears," he said.