Russia on Thursday denied US media reports that it had sent mercenaries from private military group Wagner to fight in Libya.
The New York Times reported Tuesday that some 200 Russian fighters from Wagner had arrived in Libya over the last six weeks including snipers. The group is believed to be controlled by Putin ally Yevgeny Prigozhin.
In recent years, Moscow has struck a series of military agreements with African countries and thousands of private Russian security contractors are reported to be working on the continent.
Russian contractors are reported to be fighting on the side of Libya's military strongman Khalifa Haftar, whose forces have launched an offensive against Tripoli.
The Sunday Times of Malta reported last week that Malta Customs had seized two 2,000-cubic-foot containers packed full of recently-introduced currency printed in Russia and destined for Haftar's forces.
Wagner was blacklisted by the US Treasury in 2016 for having "recruited and sent soldiers to fight alongside separatists in eastern Ukraine".
Deputy Foreign Minister Sergei Ryabkov "categorically" denied the media report.
"We are acting in the interests of the Libyan peace process," he told TASS news agency on Thursday.
"We don't believe that there are grounds for such statements and assumptions, but this is not the first time that US media spreads various tall tales" about Russia, he said.
The head of Russia's contact group to Tripoli, Lev Dengov, called the report "absolutely untrue."
Acting as a mercenary is a criminal offence for Russians.
"Such statements discredit Russia's part in the peace process," Dengov told Russian agencies.
Prigozhin is a Saint Petersburg businessman who made a fortune in catering before signing lucrative contracts with Russia's military and government.
Known as "Putin's chef", he has denied any ties to the Wagner Group.
He has also been charged by a US court with setting up an internet "troll factory" that attempted to influence the 2016 American presidential elections in favour of Donald Trump.
In 2018 Prigozhin was also indicted by the US for election interference through the "troll factory," although he denies any connection to it.