Russia denied on Monday that its state-run United Aviation Corporation (UAC) planned to bid for a $50 billion contract to replace the U.S. Air Force's fleet of air tankers, rivaling Boeing Co and Europe's EADS.

John Kirkland, a Los Angeles-based attorney, had told various news media over the weekend that UAC would announce a joint venture on Monday with a U.S. defense contractor to enter the bidding for the tanker deal.

UAC denied it had held any talks on bidding for the contract. We have not been holding, are not holding and are not planning to hold such talks, said a UAC official.

Separately, UAC vice-president Alexander Tulyakov said the attorney did not work for the company. John Kirkland is not a UAC representative and we have had no communications with him (about the tender), he told Reuters.

Russian Prime Minister Vladimir Putin and U.S. Secretary of State Hillary Clinton had not discussed any Russian role in the contract when they met on Friday, Putin's spokesman Dmitry Peskov said. It was not a topic at the talks, he told Reuters.

The U.S. Air Force has been trying for nearly a decade to replace its fleet of Boeing-built KC-135 tanker aircraft, which are close to 50 years old.

EADS , the parent company of Airbus, won a deal in 2008 to build an initial 179 tankers, only to have it canceled after auditors intervened. The Pentagon said last week that EADS had expressed possible interested in continuing to compete with Boeing for the contract.

Kirkland quoted Alexander Shishkin, who he said worked for the Russian Federal Service of Military-Technical Cooperation, as saying the U.S.-Russian joint venture being formed to bid would be announced at UAC headquarters on Monday morning.

However Shishkin, when contacted by Reuters on Monday, said he could not say anything. He would not even confirm he worked for the Federal Service of Military-Technical Cooperation. I cannot say anything until the bosses decide something, he said.

UAC's Tulyakov also said Russia was making arms sales abroad only via state arms export monopoly Rosoboronexport. We have held no discussions with them (about the tender), he added.

FANTASY

An official at the agency said that there was nobody called Alexander Shishkin listed as working there.

Kirkland had said Russian Foreign Minister Sergei Lavrov discussed a UAC bid for the tanker contract at a meeting with Clinton. Russia's Foreign Ministry declined comment on Monday.

Neither Russian nor U.S. officials mentioned at the time any discussions about a tanker bid. Clinton held a bilateral meeting with Lavrov on Thursday and met President Dmitry Medvedev and Putin on Friday separately.

Kirkland said that a Russian bid would be based on a widebody version of UAC's Ilyushin-96 aircraft, which he said would be called the Ilyushin-98.

There are some internal discussions within the UAC, but very preliminary ones, about the production of an air tanker based on the Il-96. But to talk about Russian air tankers refueling U.S. military planes -- it is from the realms of fantasy, said a UAC source, who asked not to be named.

Fewer than 30 Ilyushin-96 aircraft have been produced and the plane is considered technically inferior to Western competitors. Russian news media reported last year that production of the passenger variant had been canceled, although a cargo version is still in limited production. Russian media have made no mention of a new version of the Il-96 called the Il-98.

(Reporting by Gleb Stolyarov and Guy Faulconbridge, additional reporting by Conor Sweeney, writing by Michael Stott and Dmitry Zhdannikov; editing by David Stamp)