Roman Abramovich
Roman Abramovich\'s spokesperson has denied claims the mogul has been arrested in the FBI.

The FBI has denied reports that it has arrested Roman Abramovich during the tycoon's visit to the United States.

The Bureau said the reports, published by Russian television news service RBC, were "categorically untrue".

The denial came just minutes after Abramovich's press secretary, John Mann, issued a similar statement refuting the claims.

Mann admitted that the owner of Chelsea Football Club is in the US, but added that "the story about Roman Abramovich being arrested is NOT TRUE."

RBC is one of Russia's foremost news agencies, and reportedly has links to American media giants CNN and CNBC.

Its story provided little detail as to the circumstances of Abramovich's 'arrest', with no direct quotes provided. The reporter was also unable to clarify whether the arrest pertained to Abramovich's business dealings or the death of his former business partner, Boris Berezovsky.

Beresovsky, who lost a high-profile legal battle with Abramovich last year, died on Saturday at his Hertfordshire mansion. However investigators have said there is as yet no evidence of foul play.

Abramovich is one of the world's most high-profile businessmen, and has been owner of Chelsea football club for the last 10 years.

Shares in his company Evraz fell 3.3 percent following the reports from RBC.