The United States Senate has started the historic impeachment trial of President Donald Trump amidst acrimonious scenes among the Senators from the ruling Republican party and the opposition Democrats over the rules of the game.
The impeachment trial began on Tuesday and comes nearly a week after the House of Representatives, where the Democrats enjoy a majority, voted to send articles of impeachment against President Trump to the Senate.
In a 228-193 vote, which was mainly on party lines, the House had appointed seven impeachment managers to argue Democrats' case for removing Trump from the office.
The managers - Congressmen Adam Schiff, Jerrold Nadler, Zoe Lofgren, Hakeem Jeffries, Val Demings, Jason Crow, and Sylvia Garcia - were named by House Speaker Nancy Pelosi.
The 435-member House on December 18 charged Trump with "high crimes and misdemeanors" and impeached him for pressuring Ukraine to investigate former Vice President Joe Biden, a potential Democratic rival for the current president in the 2020 elections.
President Trump's lawyers submitted a trial brief Monday calling his impeachment by the House "a dangerous perversion" of the US constitution and demanding his immediate acquittal by the Senate.
On Tuesday, the Senate started the historic trial in "utter acrimony" as the debate was a technical one about the rules and procedures to govern the trial, The New York Times reported.
Trump's close-ally Mitch McConnell laid out ground rules that would block subpoenaing key witnesses or documents while each side makes its case -- potentially crippling prosecutors' arguments.
Flexing his solid 53-47 majority, the Republican Senate leader also made clear he would summarily block any Democratic attempts to change his rules.
"The basic structure we're proposing is just as eminently fair and even-handed," McConnell said.
Adam Schiff, the leader of the House impeachment managers prosecuting Trump, countered that the process "makes no sense" for a trial, and was designed instead to ensure evidence is never heard and Trump is exculpated.
Political experts say that Trump is likely to emerge victorious as his Republican party enjoys majority in the Senate.
This is only the third time in American history that a US President is facing impeachment trail in the Senate.
Confident of the end result of the impeachment trial, Trump was in Davos to attend the annual meeting of World Economic Forum, where he met the leaders of various countries, including Pakistan's Prime Minister Imran Khan.
The White House said that the Democrats were a joke and they have no case at all.
"The Democrats are an utter joke - they have no case, and this latest political stunt proves it. The idea that the Counsel to the President has to turn over protected documents and confidential information is ludicrous, and to imply he can't represent the President of the United States in an impeachment proceeding is completely absurd,” White House Deputy Spokesperson Hogan Gidley said.
The Democrats charged the Republican leadership in the Senate of being biased and not fair.
"The public realises how unfair the McConnell proposal is, and the pressure that we have put on them and on Republican senators has gotten them to change,” Senate Minority Leader Chuck Schumer said.
This was rejected by the GOP leaders.
“This initial step will offer an early signal to our country: Can the Senate still serve our founding purpose?” McConnell said.