A senior United States treasury official has called Russian President Vladimir Putin a "picture of corruption" who uses state assets for his own personal gain.
Adam Szubin, acting treasury secretary for terrorism and financial crimes, said in an interview with the BBC's Panorama programme that the Russian president has been amassing secret wealth for years.
"We've seen him enriching his friends, his close allies and marginalising those who he doesn't view as friends using state assets. Whether that's Russia's energy wealth, whether it's other state contracts, he directs those to whom he believes will serve him and excludes those who don't. To me, that is a picture of corruption," Szubin was quoted as saying.
Szubin declined to comment on a 2007 Central Intelligence Agency report that estimated Putin's wealth at $40bn, but he said the Russian leader's stated wealth is an underestimation.
"He supposedly draws a state salary of something like $110,000 a year," Szubin said. "That is not an accurate statement of the man's wealth, and he has longtime training and practices in terms of how to mask his actual wealth."
The Kremlin said on Tuesday brushed aside the comments.
"It's an official accusation," Putin's spokesman Dmitry Peskov told journalists in a conference call. "[Bilateral] relations are now in such a state that a lie like this is unlikely to aggravate them even further."
Putin repeatedly said he has read press reports about his immense wealth - including that he was even the world's richest man - but has denied those as nonsense.
The report came just days after a British inquiry concluded that Putin was likely to have approved a 2006 Russian intelligence operation to murder ex-KGB agent Alexander Litvinenko with radioactive polonium-210 in London.