WASHINGTON (BLOOMBERG) - The House of Representatives is preparing for an expected vote on Wednesday (Dec 18, from 9pm Singapore time) on two articles of impeachment against United States President Donald Trump.

The adoption of the measures would make him the third president in US history to be impeached and would set up a Senate trial in January.

The House Rules Committee has scheduled six hours of House floor debate before members will vote on the two articles to impeach Trump.

House members will vote on each article separately.

Before that debate, House members will use an hour to consider and will then vote on the rule that sets parameters for the debate.

"I do not want this to turn into a circus," Rules Chairman Jim McGovern said.

House Judiciary chairman Jerrold Nadler and the committee's top Republican, Doug Collins, will lead the debate.

Freshman Democrat Jared Golden of Maine has said he is going to vote for the article charging abuse of power but will oppose the other one alleging obstruction of Congress, according to the Bangor Daily News.

Mr Golden said the House investigation "clearly" found evidence that Mr Trump abused his power in an effort to damage a political opponent, the Maine newspaper quoted him as saying. "This action crossed a clear red line," he said.

The lawmaker said he was opposing the obstruction article because he doesn't believe it meets the constitutional threshold of "high crimes and misdemeanours", the newspaper said.

Senate Majority Leader Mitch McConnell has said he's "not an impartial juror" in the Senate trial that's expected after the House votes on impeaching Mr Trump.

"This is a political process," McConnell said. "I'm not impartial about this at all."

McConnell also said he's optimistic that he and Democratic leader Chuck Schumer can agree on the first phase of the Senate trial, although he added that they will differ on the second phase that could include additional witnesses.

He said the procedures for the Senate trial will be decided by 51 votes. Republicans control the Senate 53-47.

"It's pretty safe to say" that with partisan differences so strong, people will "sign up with their own side," McConnell said.