Paul Manafort talks to reporters on the floor of the Republican National Convention in Cleveland. Manafort, who joined the Trump campaign in March, served as campaign chairman from May until his resignation in August. (Matt Rourke/AP)

New corruption allegations lodged in Ukraine against President Trump’s former campaign chairman, Paul Manafort, have thrust Manafort back into the forefront of ongoing scrutiny over whether the Trump team coordinated with the Russian government to influence the U.S. election.

The allegations were disclosed Tuesday at a news conference by a Ukrainian lawmaker who said he had obtained documents showing that Manafort had attempted to hide payments he had received from the party of Ukraine’s former president, who is living in Russia and wanted on corruption charges­ in his home country.

A spokesman for Manafort called the claims “baseless” and said some of the documents released Tuesday appeared to be fabricated because the letterhead and signatures did not match those belonging to Manafort.

The spectacle in Kiev came just hours after FBI Director James B. Comey confirmed the existence of a federal probe into possible connections between Trump’s campaign and the Kremlin.

It also followed an apparent effort by the White House to distance Trump from the man who helped lead his campaign during five critical months into last summer, with White House press secretary Sean Spicer declaring Monday that Manafort had played a “limited role for a very limited amount of time” in the campaign.

(Sarah Parnass/The Washington Post)

Manafort, 67, a longtime lobbyist and Republican strategist, was hired by the Trump campaign in March 2016, a time when Trump was winning primaries but feared he could still lose the nomination if his team failed to properly master arcane convention rules and wrangle votes from Republican delegates. In May, he was named the campaign’s chairman.

From the start, there was focus on Manafort’s ties to pro-Russian figures, given Trump’s repeated calls to forge closer relations to Russian President Vladi­mir Putin and Russia’s emerging role over the summer in seeking to meddle in the U.S. election.

U.S. intelligence officials have said that the Kremlin orchestrated the politically damaging hacks of emails from the Democratic National Committee and Hillary Clinton’s campaign chairman, John Podesta.

Manafort had done business with Putin-aligned business titans and worked in Ukraine for former president Viktor Yanukovych’s political party starting in 2004. Yanukovych fled the country in 2014 amid violent street protests.

The issue of Ukraine’s relationship with Russia was a point of contention during the campaign, with Trump expressing openness to consider easing U.S. sanctions on Moscow that had been imposed after Russia’s 2014 annexation of Crimea from Ukraine.

Manafort resigned as Trump’s campaign chairman in August, after the New York Times reported that his name appeared in a “black ledger” that showed he was paid $12.7 million in secret cash payments from Yanukovych’s party. Manafort has denied receiving the payments and said he is the victim of political infighting in Ukraine.

Now, Manafort has come under scrutiny in an FBI investigation into possible foreign corruption involving Ukrainian politics, according to people familiar with the matter. The Ukraine corruption investigation is related to the broader counter­intelligence investigation into alleged contacts between Trump campaign officials and Russian officials, these people said.

But Manafort vehemently denies any involvement in the Russian efforts and has told people close to him that he is eager to testify before congressional committees investigating Moscow’s intervention in the election.

In a statement, Manafort said he was the victim of a “blatant attempt to discredit me and the legitimacy of the election of President Trump.”

“I had no role or involvement in the cyber­attack on the DNC or the subsequent release of information gained from the attack, and I have never spoken with any Russian Government officials or anyone who claimed to have been involved in the attack,” he said. “The suggestion that I ever worked in concert with anyone to release hacked emails or sought to undermine the interests of the United States is false. Despite the constant scrutiny and innuendo, there are no facts or evidence supporting these allegations, nor will there be.”

[Inside Trump adviser Manafort’s world of politics and global financial dealmaking]

The new allegations against Manafort were leveled by Serhiy Leshchenko, a lawmaker and journalist, who on Tuesday released a copy of what he said was an invoice on letterhead from Manafort’s consulting company, based in Alexandria, Va., dated Oct. 14, 2009, to a Belize-based company for $750,000 for the sale of 501 computers.

On the same day, Manafort’s name is listed next to a $750,000 entry in the “black ledger” released by anti-corruption investigators in August. The list was found at the party headquarters in the turmoil after Ukraine’s 2014 revolution.

Leshchenko alleged that Manafort falsified an invoice to the Belize company to legitimize the $750,000 payment to himself.

Nazar Kholodnytskyi, a deputy prosecutor general of Ukraine whose department specializes in corruption cases, said in an interview Tuesday that the documents hadn’t been confirmed by law enforcement or, to his knowledge, submitted for examination. There is an ongoing investigation into the black ledgers, he said, but Manafort was not a target of that investigation.

Manafort’s spokesman, Jason Maloni, said the new documents released Tuesday appear to be fabricated. “We have seen some of the new documents and they are not Paul’s letterhead or Paul’s signature,” he said.

Maloni added that Leshchenko’s claims should be “summarily dismissed.”

Leshchenko’s name has emerged separately in a cache of more than 285,000 personal messages apparently stolen from the iPhone of Manafort’s daughter, Andrea Manafort, 31, and dumped in February on a website used by cyberhackers.

Maloni said Manafort has confirmed that his daughter’s phone was hacked and that some of the texts are authentic, but he has declined to authenticate the entire cache. Maloni said Andrea Manafort declined to comment.

The posted texts show Manafort had received a blackmail email purportedly from Leshchenko in August, threatening to release information about Manafort’s work in Ukraine. Leshchenko has said he did not send the email. Maloni said Manafort did not know who was behind the threat but had turned the matter over to his lawyer.

In her texts, Andrea Manafort dismissed the idea that her father would have taken cash as described in the Ukrainian ledger. “It’s just a bunch of hogwash,” she wrote a few days after he resigned. “My dad is a lot of things but he isn’t stupid.”

But she also apparently expressed deep reservations about his work overseas.

“Don’t fool yourself,” she wrote to her sister in 2015, according to the posted texts. “The money we have is blood money.”

Andrea Manafort also portrayed her father as being at the center of Trump’s campaign, texting a friend in April that he was Trump’s “right hand man,” one posted message said.

“He’s super tight w the trumps. All the kids call him all the time,” she wrote, according to the messages posted online.

Roth reported from Kiev, Ukraine. Devlin Barrett contributed to this report.