About Oleg Deripaska, the Russian billionaire who worked with Paul Manafort Work alleged to have included seeking to "benefit the Putin government."

 -- Since becoming one of Russia’s richest men in the early 2000s, billionaire metals magnate Oleg Deripaska has put his wealth at the Kremlin’s service and even once himself as a public whipping boy for the country’s president, Vladimir Putin.

When the Kremlin wanted Olympic facilities for the 2014 games in Sochi, Deripaska built them at what he said was almost a loss. And when international media mocked Russia over the huge number of stray dogs in the town, he opened a shelter for them.

Today, the Associated Press reported that Donald Trump’s former campaign manager, Paul Manafort, worked for Deripaska, for several years starting more than a decade ago, to advance the interests of Putin. The AP said it had obtained documents showing Manafort pitched a confidential strategy plan, outlining how he could influence politics, the media and business in the Kremlin’s favor in the United States and across Russia’s former satellite states, to Deripaska in 2005.

Manafort confirmed to AP that he worked for Deripaska on "business and personal matters" for a decade, but denied it involved "representing Russian political interests." If he did make such a pitch, though, Manafort would have had good reason to think it would reach Putin.

Deripaska is one of the richest and best-known of Russia’s oligarchs, a business titan who emerged from the economic chaos of the 1990s. Estimated by Forbes to be worth $5.1 billion, Deripaska is considered one of the "court oligarchs" of Putin’s Kremlin, expected to put up cash and execute state projects when called upon.

Deripaska was among a group of Kremlin-linked businessmen who complained at the Sochi Olympics that they were effectively footing the bill for the facilities they were building.

Raised in modest circumstances in a Cossack village and then educated as a nuclear physicist, Deripaska’s is a classic story of the Putin-era oligarchs who gained control of Russia’s key assets for bargain prices and then held onto them through the often violent, mafia-ridden business disputes that followed Communism’s end.

Deripaska, 49, notably made his fortune in the cut-throat metals industry, where contract killings were so common the struggle for assets became known as the "Aluminium Wars."

Deripaska appeared to emerge unscathed, coming to monopolize the bulk of Russia's aluminum production -- a feat few believe could have been achieved without becoming entangled in some of the darker practices of the time. He still owns the vast aluminium company Rusal.

In 2006, the U.S. State Department denied Deripaska a visa; though it declined to say why, U.S. officials at the time told Reuters he was denied entry to the U.S. amid concerns about his links to organized crime.

Deripaska doesn’t deny he has, at times, had to collaborate with suspected mafia figures. In 2012, he settled a $1 billion court case with a man he said had acted as his mafia cover in the 1990s. Deripaska said he had no choice but to work with the man. Such were the times, he said.

Putin Links

Deripaska’s closeness to Putin is open to debate. He operates at the highest levels of the Russian elite and is married into it -- to the daughter of one of former President Boris Yeltsin's chiefs-of-staff.

A 2006 U.S. embassy cable published by Wikileaks described him as "among the 2-3 oligarchs Putin turns to on a regular basis" and "a more or less permanent fixture on Putin's trips abroad."

Despite his regular contact with Putin, he is not considered personally close to the president or part of his inner circle.

One famous incident has come to characterize Deripaska’s relationship with the Kremlin.

In 2009, one of Deripaska’s factories had halted production because he was engaged in a business quarrel with his partners. Putin flew to the factory in the town of Pikaleva and on national television humiliated Deripaska. In front of the cameras, Putin called Deripaska and the other owners "cockroaches" taking people hostage through their greed. He forced Deripaska there and then to sign an agreement ending the quarrel, tossing a pen contemptuously at him.

The scene was a classic piece of Putin theater, meant to underline how he has brought the oligarchs to heel. It also appeared to highlight Deripaska’s position as servant of the Kremlin, at the mercy of its favor.

Deripaska, though, has benefited from the relationship as well. In 2008, his company Rusal received a $4.5 billion bailout loan from the government to save it from defaulting on its loans to a group of Western banks.

Relationship with Manafort

The origins of Deripaska’s relationship with Manafort are murky. The AP report suggests that Manafort’s work for Deripaska began at the latest in 2005, when he was already advising Ukraine’s now toppled pro-Russian president, Viktor Yanukovych.

There have been suggestions that Deripaska was responsible for launching Manafort’s work with Yanukovych and his political party, the Party of Regions. Scrutiny over payments to Manafort for this work last summer contributed to his resignation from Trump’s campaign.

A senior figure from Yanukovych’s party, who requested anonymity because he did not want to risk harming his relationship with Manafort, told ABC News last year that as far he remembered it had been Deripaska who connected Manafort with the party. The AP report also said at least some of Manafort’s work in Ukraine was directed by Deripaska and not local political interests there, citing the memos and people with direct knowledge of the work.

Manafort was already known to have done business with Deripaska.

In 2007, around the time Deripaska was denied a U.S. visa, Manafort and his long-time business partners, Rick Davis and Rick Gates, invited the oligarch to join a Ukrainian investment through their fund Pericles Emerging Partners Limited, registered in the Cayman Islands. Deripaska invested $19 million, but the deal prompted the two to fall out, according to court documents filed by Deripaska's lawyers in 2014.

Under severe financial pressure in 2008, Deripaska tried to recover his money, finally launching a lawsuit against Manafort and the others. In the filing, the oligarch's lawyers accused Manafort and his partners of having "simply disappeared."

That quarrel resurfaced after Manafort began working for the Trump campaign, the AP reported, with Deripaska’s representatives publicly pledging to recover his money. But after Trump was elected, the representatives began refusing to comment on the case, AP reported.

Editor’s Note: This story has been updated to correct the date that Deripaska’s visa was revoked to the year 2006 and to note that Rusal received a $4.5 billion bailout to save it from defaulting on loans to Western banks.