Republican senators are sniping at each other on the floor of the Senate according to Fox News Capitol Hill reporter Jason Donner.

Voices were raised, with Senator Ron Johnson reportedly telling Senator Mitt Romney that he blamed him for the trial not being over today.

Senator Dan Sullivan sits between the two on the floor of the chamber.

Ahead of the vote on witnesses, Trump defence lawyer Michael Van der Veen said that he would need to depose as many as one hundred witnesses — including Speaker Nancy Pelosi and Vice President Kamala Harris — saying that it would have to be in person at his office in Philadelphia, not via Zoom.

There was audible laughter from senators, which Mr Van der Veen did not appreciate.

Earlier Mr Van der Veen appeared to get angry to the point he needed to take his own advice and cool down for a moment.

Griffin Connolly reports for The Independent from Washington, DC.

Five Republicans voted in favour of having witnesses appear before the Senate. Initially, they were senators Susan Collins, Lisa Murkowski, Mitt Romney, and Ben Sasse. Trump loyalist Lindsey Graham then changed his vote to ‘Aye ‘ bringing the number of yes votes to 55.

Mr Graham provided some context to his decision about an hour before the vote.

The Senate has now finished voting on whether to allow witnesses, with 55 voting for it compared to 45 against.

Former federal prosecutor Renato Mariotti called the move a “game changer”, coming as it does after new evidence emerged that Donald Trump sided with the insurrectionists during a phone call with senior Republican Kevin McCarthy.

It means a final vote on Mr Trump’s guilt or innocence is now very unlikely to happen today.

A vote as to whether to call witnesses in Donald Trump’s impeachment trial appears to have passed, after Susan Collins voted yes. It only requires one Republican to defect if all Democrats opt for witnesses, which appears to be the case.

It’s fair to say Mitch McConnell’s apparent decision to vote to acquit Donald Trump has not gone down well with critics.

The Senate minority leader in an email to colleagues, as addressed in blog posts below, wrote that it was a “close call”, but that he believed that Senate lacked the jurisdiction to try Mr Trump’s actions, because he is no longer in office.

But Mr McConnell was also damning of the former president, and appeared to suggest he could face criminal prosecution instead of conviction by Congress.

The fifth day of Donald Trump’s impeachment trial has begun, with the former president’s lawyers arguing senators should vote against calling senators.

But, they say if witnesses are called, Mr Trump’s team will “need over a hundred depositions”.

Democratic congressman Jamie Raskin, the lead impeachment manager, counters that there is only one witness who the defence should really be interviewing; their own client.

Senate minority leader Mitch McConnell has confirmed that he will vote to “acquit” former President Donald Trump at his impeachment trial on Saturday, while calling the decision a “close call”.

In an email to colleagues on Saturday morning that was obtained by Politico, Mr McConnell wrote: “As I have said for come time, today’s vote is a vote of conscience and I know we will all treat it as such.

“I have been asked directly by a number of you how I intend to vote, so I thought it right to make that known prior to the vote. While a close call, I am persuaded that impeachments are a tool primary of removal and we therefore lack jurisdiction.”

Mitch McConnell will vote to acquit Donald Trump, but was damning of the former president’s conduct during the January 6 insurrection in an email obtained by Politico.

“Colleagues – as I have said for some time, today’s vote is a vote of conscience and I know we will all treat is as such,” the Senate minority leader wrote.

“I have been asked directly by a number of you how I intend to vote, so though it right to make that known prior to the final vote.

“While a close call, I am persuaded that impeachments are a tool primarily of removal and therefore we lack jurisdiction.”

Mr McConnell concluded by suggesting Mr Trump could be criminally prosecuted for his role in the riot.