The US Senate has rejected repeated Democratic attempts to secure new evidence in President Donald Trump's impeachment as his trial began.
Senate Majority leader Mitch McConnell meanwhile backed off on a plan to fast-track the hearings after coming under pressure from fellow Republicans.
Democrats said this would have been no less than a cover-up.
Mr Trump is charged with abuse of power and obstructing the congressional inquiry. He denies wrongdoing.
At the World Economic Forum in Davos, Switzerland, on Tuesday, Mr Trump dismissed the accusations against him as "just a hoax".
Senators have taken oaths to act as impartial jurors, hearing arguments for six hours a day, six days a week in a trial presided over by the US Chief Justice, John Roberts.
Trial proceedings on the first day ran late into the night.
BBC
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Donald Trump has confirmed that he will not take part in Republican presidential debates with his rivals in the race for the White House.