The Republican-controlled U.S. House of Representatives is expected to vote on Wednesday to formalize its impeachment inquiry of Democratic President Joe Biden, a Republican leadership aide said on Monday.

The aide spoke on condition of anonymity because official plans for floor action remained fluid. Earlier on Monday, a Republican lawmaker said House Speaker Mike Johnson disclosed plans for a Thursday vote at a closed-door meeting, a time frame that had also been echoed by other Republicans.

The House is due to leave Washington on Thursday for a year-end holiday break of more than three weeks.

House Republicans accuse the Democratic president and his family of improperly profiting from policy decisions Biden participated in as vice president during President Barack Obama's 2009-2017 administration.

They have also accused the U.S. Department of Justice of inappropriately interfering with an investigation into Biden's businessman son Hunter Biden. The Justice Department denies wrongdoing.