Donald Trump has become the third US president in history to be impeached.
The US House of Representatives voted to impeach on both charges of abuse of power and obstruction of Congress after hours of debate.
However minutes after the crucial votes the process was thrown into confusion when House Speaker Nancy Pelosi refused to say when or whether she would send the articles of impeachment to the Senate for trial.
She said there needed to be clearer picture of how the Senate would conduct proceedings and that Senate Majority Leader Mitch McConnell and Minority Leader Chuck Schumer were negotiating over the conduct of the trial.
— Nancy Pelosi (@SpeakerPelosi) December 19, 2019
Ms Pelosi defended the decision to impeach the 45th president, saying: "I view this vote as something that we did to honour the vision of our founders to establish a republic, the sacrifice of our men and women in uniform to defend our democracy and that republic, and the aspirations of our children that they will always live in a democracy and that we have tried to do everything we can to make sure that is their reality."
The vote on the first of the two articles - abuse of power - came in as 230 in favour and 197 against.
The second vote - obstruction of justice - was carried by 229 to 198.
Donald J. Trump swore an oath to faithfully execute his office and protect and defend the Constitution.
Has he honored this sacred obligation? The evidence is uncontested:
Trump sacrificed our national security to cheat in the next election.
And for that, he must be impeached. pic.twitter.com/IJ8J5o1APH
— Adam Schiff (@RepAdamSchiff) December 18, 2019
Two Democrats voted against the charges - Jeff Van Drew of New Jersey and Collin Peterson of Minnesota - while no Republicans voted to impeach the president.
Following the impeachment, the White House said Mr Trump "is prepared for the next steps and confident that he will be fully exonerated" in the Senate trial.
Even if it does go to the Senate, it is unlikely Mr Trump will become the first president to actually be removed from office by the process.
The upper house is controlled by members of his own Republican Party, who are unlikely to remove him.
As events unfolded in Washington the president was speaking to the faithful at a campaign rally in Michigan.
"With today's illegal, unconstitutional and partisan impeachment, the do nothing Democrats - and they are do nothing, all they want to do is focus on this," he said.
"What they could be doing... are declaring their deep hatred and disdain for the American voter. This lawless, partisan impeachment is a political suicide march for the Democrat Party.
"Have you seen my polls in the last four weeks? It's crazy. You know why? Because people, you know, we have an election right down the road.
"I announced three months ago that I'm running, right? I'll give you a little clue. I announced because, I figured, once they announced they'd never impeach, nobody would be so stupid. But they've been trying to impeach me from day one."
He later tweeted a photo of himself, with the caption: "In reality they're not after me they're after you - I'm just in the way", without elaborating.
— Donald J. Trump (@realDonaldTrump) December 19, 2019
Only two presidents have been impeached before Mr Trump - Andrew Johnson in 1868 and Bill Clinton in 1998.
Richard Nixon resigned over the Watergate scandal instead.