Republicans leading an impeachment inquiry of US President Joe Biden have detailed foreign payments to members of his family in their first hearing but have not provided evidence that the Democratic president personally benefited.

The initial impeachment hearing by the US House of Representatives Oversight Committee served as a review of evidence that Republicans have gathered so far about foreign business ventures by Biden’s troubled son Hunter Biden, 53, which they say shows that Biden’s family members were selling access.

“The American people demand accountability for this culture of corruption,” House Oversight Committee chair James Comer said.

He said Biden had lied about family members’ business dealings and had not walled them off from his official duties.

Democrats and several independent witnesses said there was no proof that Biden had received any of those payments or otherwise engaged in improper behaviour while he was vice president from 2009-2017.

The White House has denied wrongdoing and dismissed the probe as politically motivated.

“If Republicans had a smoking gun or even a dripping water pistol they would be presenting it today. But they’ve got nothing,” said Jamie Raskin, the panel’s top Democrat.

Biden is campaigning for re-election in what will be a likely rematch with Republican Donald Trump, who is preparing for four upcoming criminal trials on a range of charges, from trying to overthrow his 2020 election defeat to mishandling classified documents after leaving office.

Democrats prominently displayed a clock counting down the minutes until midnight on Saturday, when the US government will enter its fourth partial shutdown in a decade if Congress fails to pass legislation to fund federal agencies.

George Washington University professor Jonathan Turley and forensic accountant Bruce Dubinsky said the panel had enough evidence to open an impeachment inquiry but did not have enough evidence to justify impeachment charges.

Another law professor, Michael Gerhardt of the University of North Carolina, said he had not heard credible evidence to justify the probe and warned the panel that it was being driven by partisan concerns.

A fourth witness, former Justice Department official Eileen O’Connor, said she thought the department had soft-pedalled a criminal investigation of Hunter Biden, who faces gun charges after years of struggling with drug and alcohol addiction.

Republicans allege Biden and his family profited from policies he pursued as vice president during former US president Barack Obama’s administration between 2009 and 2017.

It is unclear if House Republicans, who have a narrow 221-212 majority, would have the votes at the end of the inquiry to support actual impeachment.

But even if that vote succeeded, it is highly unlikely that the Senate, where Democrats hold a 51-49 majority, would vote to remove Biden from office.

At the centre of the investigation are allegations that Biden, as vice president, pressured Ukraine to fire a top prosecutor to shield Burisma, a company for which Hunter Biden was on the board of directors.

Numerous US and foreign officials have said Biden was carrying out official policy to fight corruption in Ukraine.

House Republicans have said they plan to seek personal and business bank records for Hunter Biden and James Biden, the president’s brother.

Comer cited payment records from Chinese citizens to Hunter in 2019, listing Joe Biden’s home address in Delaware as the beneficiary address.

Republicans have not provided evidence that the elder Biden received the money.

“Once again Rep Comer peddles lies to support a premise – some wrongdoing by Hunter Biden or his family – that evaporates in thin air the moment facts come out,” Hunter Biden’s lawyer Abbe Lowell said in a statement on Thursday.

Lowell said the money in question was a loan and that the address listed was the address on Hunter Biden’s driver’s licence at the time.

The White House said Republicans should focus on reaching a deal to keep the government open on October 1, the start of the new fiscal year.

-AAP