* Sources confirm the U.S. extracted an agent from Russia
* Kremlin plays down significance of alleged U.S. spy
* Said he was fired years ago and was not senior
* Alleged agent's Virginia address published in Russia (Adds comments by Pompeo and former CIA officer)
By Andrew Osborn and Mark Hosenball
MOSCOW/LONDON, Sept 10 (Reuters) - The Kremlin played down reports of a CIA spy inside Russia's presidential administration, but said an official identified by Russian media as the likely U.S. mole had worked there although he did not have access to President Vladimir Putin.
CNN reported on Monday that the United States had successfully extracted one of its highest-level covert sources inside Russia in 2017.
Two sources familiar with U.S. monitoring of Russian activities confirmed to Reuters that such a CIA informant did exist inside the Russian government and had been extracted and brought to the United States.
The sources indicated that U.S. officials were seriously concerned that Kremlin officials had made public what they claimed was the individual's name.
Russian daily newspaper Kommersant said on Tuesday the official may have been a man called Oleg Smolenkov, who is reported to have disappeared with his wife, Antonina, and three children while on holiday in Montenegro in June 2017.
It cited unnamed Russian law enforcement officials as saying Moscow had initially opened an investigation into his suspected murder in Montenegro before concluding he was alive and living abroad.
Kommersant published a picture of a house in Virginia which it said had been bought later by the Smolenkovs and linked to details of the property's purchase, including its exact address, in a real estate listing and a local county tax filing.
One U.S. official familiar with the background to the story said it was not necessarily totally stupid or against standard spy practice for a defector to buy property in his own name. He did not say why.
But now that the story had become public it was highly likely the U.S. government would have to make serious efforts to protect the defector, said the source, who did not dispute the mole was Oleg Smolenkov.
U.S. Secretary of State Mike Pompeo, speaking at a White House briefing, dismissed reports that the CIA pulled the informant out of Russia over concerns the asset's identity could be exposed.
"The reporting there is factually wrong," said Pompeo, without elaborating.
Daniel Hoffman, a former CIA station chief with deep expertise on Russia, said the informant is a marked man because Putin cannot risk Russian officials “thinking they can get away with betraying Russia.”
“This means that guy has a bullseye on his face,” said Hoffman, who noted that a 2006 law empowers Putin to order extrajudicial killings outside Russia. “When Vladimir Putin has known about high-value sources who he says betrayed Russia, he tried to kill one of them with a Soviet nerve agent and he killed another with polonium."
He was referring to the 2018 attempted murder in Britain of Sergei Skripal, a former Russian military intelligence officer and double agent for British intelligence, with the nerve agent Novichok and the 2006 killing with radioactive polonium of Alexander Litvinenko, a Russian intelligence officer who received political asylum in Britain.
Asked about the matter, Kremlin spokesman Dmitry Peskov said that Smolenkov had worked in the Russian presidential administration but had been fired in 2016/17.
"It is true that Smolenkov worked in the presidential administration, but he was fired several years ago. His job was not at a senior official level," said Peskov.
Smolenkov did not have direct access to Putin, Peskov added, declining with a laugh to confirm whether he had been a U.S. agent or not.
"I can’t confirm that. ... I don’t know whether he was an agent. I can only confirm that there was such a person in the presidential administration, who was later sacked.
"All this U.S. media speculation about who urgently extracted who and saved who from who and so on - this is more the genre of pulp fiction, crime reading, so let's leave it up to them," said Peskov.
Smolenkov at different times worked at the Russian Embassy in the United States, in the Russian government administration and in the Russian presidential administration, open-source documents inside Russia show.
His wife worked in another Kremlin department, Kommersant said.
It cited some unnamed sources as saying they thought Smolenkov had only done routine work and could not have passed anything more than "two-bit rumours" to the Americans.
But other sources were cited as saying that Smolenkov worked with and enjoyed the trust of Putin foreign policy aide Yuri Ushakov who does have access to the Russian leader.
"This is serious," it cited one unnamed Russian official as saying.
Russian Foreign Minister Sergei Lavrov said separately on Tuesday he had never heard of Smolenkov.
"I have never seen this man, have never met him, and have never monitored his career or movements," Lavrov said.
CNN reported on Monday that the U.S. decision to extract its informant had occurred soon after a May 2017 meeting in the Oval Office in which U.S. President Donald Trump had discussed highly classified intelligence with Lavrov.
Lavrov said on Tuesday that nobody had divulged any secrets to him at the meeting with Trump.
A U.S. government source also insisted that Trump did not disclose secrets, such as the informant's existence or identity, at any meeting with Russian officials. (Additional reporting by Tom Balmforth and Rinat Sagdiev in Moscow and Jonathan Landay and Steve Holland in Washington; Editing by Giles Elgood and Jonathan Oatis)