The jury in the trial of former Donald Trump campaign manager Paul Manafort is expected to start deliberating on Thursday after hearing he had "a huge dumpster of hidden money" abroad.

Special Assistant US Attorney Greg Andres gave his closing statement in federal court in Alexandria, Virginia, in the first trial to come out of Special Counsel Robert Mueller's investigation of Russian meddling in the 2016 presidential election.

The charges against Manafort involve tax and bank fraud, not possible collusion between Russia and Donald Trump's campaign for president.

The star witness against Manafort was Rick Gates, his former right-hand man, who was indicted along with Manafort but pleaded guilty and agreed to cooperate with the government.

The defence has portrayed Gates as a lying thief who had his hand in the "cookie jar" and was only trying to reduce his own sentence.

But Andres said Gates' testimony was corroborated by other evidence, including nearly 400 exhibits.

"The star witness in this case is the documents," Andres told the jury.

"That wasn't a cookie jar," he added, referring to the tens of millions of dollars Manafort held overseas. "It was a huge dumpster of hidden money in foreign bank accounts."

Prosecutors say Manafort, 69, tried to mislead bankers with doctored financial statements in 2015 and 2016 to secure more than $US20 million ($A28 million) in loans and failed to pay taxes on more than $US15 million ($A21 million) that he earned as a political consultant in Ukraine.

In the defence's closing argument, Manafort's lawyers sought to emphasise the idea that Manafort did not knowingly break the law - a requirement for conviction - and was failed by the bookkeepers, accountants and other professionals in whom he trusted his financial affairs.

"Sometimes the people we rely on are trustworthy. Sometimes they are not," said lawyer Richard Westling.

The defence took particular aim at Gates, who said he helped Manafort doctor financial statements, hide foreign income and evade hundreds of thousands of dollars in income taxes.

Manafort's attorneys have portrayed Gates as living a secret life of infidelity and embezzlement.

"He came in here trying to look all clean shaven," Downing said. "He came in here and tried to get one over on you."

Manafort made millions of dollars working for pro-Russian Ukrainian politicians before taking an unpaid position with Trump's campaign.

He was on the campaign team for five months and led it in mid-2016 when Trump was selected as the Republican presidential nominee.

Prosecutors say Manafort hid money in offshore bank accounts and then used it to pay for over $US6 million ($A8.3 million) in New York and Virginia real estate, items such as antique rugs and fancy clothes, including a $US15,000 ($A20,793) jacket made of ostrich skin.