(Reuters) - The U.S. House of Representatives voted on Wednesday to formally authorize its ongoing impeachment inquiry into President Joe Biden, as Republicans unite behind the effort even though they have yet to find evidence of wrongdoing by the Democrat.

The Republican-controlled chamber voted 221-212 along party lines to approve the probe, which is examining whether Biden improperly benefited from his 53-year-old son Hunter Biden's foreign business dealings, hours after the younger Biden refused a call to testify behind closed doors.

The White House has dismissed the inquiry as unsubstantiated by facts and politically motivated. Biden is preparing for a possible 2024 election rematch with his Republican predecessor, Donald Trump. Trump is the first president in U.S. history to be impeached twice and is currently preparing for four upcoming criminal trials.

The effort will almost certainly fail to remove Biden from office. Even if the House votes to impeach the president, the Senate would then have to vote to convict him on the charges by a two-thirds vote — a near-impossibility in a chamber where Biden's fellow Democrats hold a 51-49 majority.

But it could help Republicans highlight their allegations of corruption through much of the 2024 campaign.

The vote comes three months after Republicans informally began the probe and is not a required step to remove a president or other official from office.

However, authorization could give Republicans more legal authority to force Biden's administration to cooperate and could help to counter accusations from Democrats who say it lacks legitimacy.

House Republicans allege that Biden and his family profited from his actions when he served as President Barack Obama's vice president from 2009 to 2017 and they have zeroed in on his son's business ventures in Ukraine and China during that period.

They have turned up evidence that the younger Biden led clients to believe that he could provide access to the vice president's office. But they have not provided evidence that Biden took any official actions to help those businesses or benefited financially from them.

Biden in a statement chastised House Republicans for not acting on his request for any of his domestic priorities or providing emergency funding for Ukraine and Israel.

"House Republicans are not joining me. Instead of doing anything to help make Americans' lives better, they are focused on attacking me with lies," Biden said.