House Republicans says 'top priority' to probe Biden familyOne day after retaking a majority in the US House of Representatives, Republicans have said they will investigate the president's family as a "top priority".
The lawmakers said the inquiry would focus on overseas business dealings of the president's son, Hunter Biden.
The 52-year-old is already under federal investigation, but has so far not faced any charges.
The younger Biden is not involved with the administration in any capacity.
But top Republicans insist their inquiry will determine the extent of Joe Biden's alleged involvement in his son's business dealings, including during the elder Biden's time as vice-president.
In an interim report released at a press conference on Thursday, they argued that the president had lied to the American people about his alleged involvement in his family's business dealings.
"The president's participation in enriching his family is, in a word, abuse of the highest order," said James Comer, the incoming chairman of the House Oversight Committee.
"I want to be clear: this is an investigation of Joe Biden, and that's where our focus will be next Congress."
They accused Hunter Biden of crimes including tax evasion and wire fraud, but did not announce any immediate plans to summon him to testify.
Christopher Clark, a lawyer for Hunter Biden, told BBC News his client had no comment about the Republican announcement.
Mr Comer was joined at the press conference by congressman Jim Jordan, who is expected to become chairman of the House Judiciary Committee.
The Ohio Republican later tweeted: "The Biden Family's business deals are a national security threat."
Officials with the Democratic National Committee have hit back by circulating a memo that refers to Mr Comer, a Kentucky congressman, as "a Trump apologist who has made clear that his phony investigations are political exercises designed to hurt President Biden".
The White House said the inquiries were politically motivated.
Spokesman Ian Sams said: "Instead of working with President Biden to address issues important to the American people, like lower costs, congressional Republicans' top priority is to go after President Biden with politically motivated attacks chock-full of long-debunked conspiracy theories."
The newly announced investigation is one of many that House Republicans could lead. Others include the Biden administration's troop withdrawal from Afghanistan and its handling of the Covid-19 pandemic.
The select committee investigating the 6 January 2021 riot by Trump supporters on Capitol Hill will be dissolved when the new Congress takes over.
If Democrats had kept the House, the probe into efforts by Trump supporters to block Joe Biden from taking office would have continued.
The Republican party conference has nominated California Republican Kevin McCarthy, its current minority leader, as its choice for House Speaker when a new Congress convenes in January.
If elected, he would succeed long-time Democratic leader Nancy Pelosi, who announced on Thursday that she is stepping down from her leadership post.
Mr McCarthy has suggested that a Republican majority will pull back on funding for Ukraine, but he must contend with a narrow majority in the chamber.
Democrats will meanwhile retain power in the Senate, the upper chamber of Congress.