FBI won't help Ukraine question Paul Manafort -- who's implicated in overseas money laundering scheme

President Donald Trump's former campaign chairman, Paul Manafort, is wanted for questioning in Ukraine -- but prosecutors there are confused why the FBI won't help them.

Investigators in the U.S. and Ukraine want to question Manafort in separate investigations related to his work for a pro-Russian political party, but the U.S. Department of Justice has ignored repeated requests for help from the former Soviet republic, reported Politico.

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Manafort resigned as Trump's campaign chairman in August over allegations that he had been paid $12.7 million illegally by the pro-Russia Party of Regions.

A Ukrainian lawmaker released new financial documents Tuesday from the party's "black ledger" that show Manafort laundered those payments using offshore accounts in Belize and Kyrgyzstan, reported the Washington Post.

Serhiy Leshchenko, a Ukrainian lawmaker and investigative journalist, released a copy of an invoice on Manafort's consulting company letterhead that shows a payment of $750,000 for the sale of 501 computers to a Belize-based company.

On that same day, Oct. 14, 2009, Manfort's name is listed in a $750,000 entry in the black ledger, which was found at the party headquarters during the 2014 riots, that investigators see as a party slush fund.

Manafort has accused Leshchenko of attempting to blackmail him before he stepped down from the Trump campaign.

The FBI has an evidence-sharing agreement with the Ukrainian prosecutor’s office, which has sent two formal requests for help in questioning Manafort, followed by five "reminders."

One of those letters was sent directly to FBI Director James Comey, who confirmed Monday that his agency was investigating possible links between the Trump campaign and Russia.

Comey refused to comment on Manafort, but the White House distanced itself from Trump's former campaign chair after Democratic lawmakers focused much of their questioning on his role during a congressional hearing.

Serhiy Gorbatyuk, who heads the department for special investigations within the General Prosecutor’s Office of Ukraine, hopes to question Manafort about his relationship to disgraced former president Viktor Yanukovych during 2014 riots that drove him from power.

That investigation has been slowed without the cooperation of the Justice Department, which oversees the FBI.

“I would call it a lack of understanding why it's taking so long to fulfill our requests,” Gorbatyuk told Politico.

Comey declined to comment on the delay during his congressional testimony, but a federal law enforcement official told Politico that participation in mutual legal assistance treaties often takes time to negotiate.

Gorbatyuk hopes to interview Manafort, who is not a suspect in the investigation, and a Washington law firm that assisted Yanukovych in a legal battle with an imprisoned political rival.

Manafort has denied any communications with Russian government officials or anyone involved in the hacking of the Democratic National Committee or Hillary Clinton's campaign team.

“Despite the constant scrutiny and innuendo, there are no facts or evidence supporting these allegations, nor will there be," Manafort said.

Leshchenko was not aware of a formal investigation of the money laundering documents by Ukrainian prosecutors, and he declined to say whether he'd discussed them with U.S. law enforcement agencies.