Democrat Pelosi sets Trump impeachment vote for Wednesday

US lawmakers will take a historic and highly anticipated vote on impeaching President Donald Trump on Wednesday, the leading Democrat in Congress said.

"Tomorrow the House of Representatives will exercise one of the most solemn powers granted to us by the Constitution as we vote to approve two articles of impeachment against the president of the United States," House Speaker Nancy Pelosi said in a letter to Democratic colleagues on Tuesday.

"During this very prayerful moment in our nation's history, we must honour our oath to support and defend our constitution from all enemies, foreign and domestic," she added.