President Trump has fired his third Chief of Staff Mick Mulvaney, and plans to replace him with a key ally in Congressman Mark Meadows.

Meadows was a huge supporter of Trump during the impeachment process, with the president referring to him as an 'extraordinary guy' during his acquittal 'victory lap'.

‘I am pleased to announce that Congressman Mark Meadows will become White House Chief of Staff,’ the president tweeted on Friday.

‘I have long known and worked with Mark, and the relationship is a very good one.

The president continued: ‘I want to thank Acting Chief Mick Mulvaney for having served the Administration so well.

Congressman Mark Meadows (left) will replace Mick Mulvaney (right) as the new White House chief of staff, President Trump announced on Friday

‘I am pleased to announce that Congressman Mark Meadows will become White House Chief of Staff,’ the president tweeted on Friday. ‘I have long known and worked with Mark, and the relationship is a very good one...'

The president continued: ‘I want to thank Acting Chief Mick Mulvaney for having served the Administration so well. He will become the United States Special Envoy for Northern Ireland.’

‘He will become the United States Special Envoy for Northern Ireland.’

Neither Meadows or Mulvaney were with the president on Air Force One during his trip to the Centers for Disease Control and Prevention in Atlanta.

Meadows will be the fourth to serve as Trump's chief of staff.

Mulvaney held the role as acting chief of staff following the resignation in December 2018 of John Kelly. Kelly took over the job from Reince Preibus, who served under Trump between January 20 and July 31, 2017.

He lasted a little over a year in the position and was never able to shake free from the 'acting' label.

Mulvaney held the role as acting chief of staff following the resignation in December 2018 of John Kelly (left). Kelly took over the job from Reince Preibus (right)

The long-rumored move makes Meadows, who announced he was not seeking reelection for his House seat from North Carolina, effectively Trump's fourth chief of staff since taking office in 2017.

Meadows has had a big impact in the lower chamber of Congress during his tenure in co-founding the House Freedom Caucus in 2015 and in that same year he filed a motion that eventually led to then-House Speaker John Boehner resigning.

Mulvaney, who served in Congress for South Carolina's 5th district until 2017, also co-founded the Freedom Caucus.

Between 2017-2019 – when the House, Senate and White House were all GOP-led – Meadows and fellow Freedom Caucus founder and Trump ally Representative Jim Jordan of Ohio had a lot of power in the House.

Between 2017-2019 – when the House, Senate and White House were all GOP-led – Meadows and fellow Freedom Caucus founder and Trump ally Representative Jim Jordan of Ohio had a lot of power in the House

Rep. Mark Meadows brought Lynne Patton, an African-American administrator in the Department of Housing and Urban Development who used to work for the Trump Organization (the woman standing behind him) to Michael Cohen's hearing to prove Trump was not racist

'The hardest decision for me is that when you're in the fight, you enjoy staying in the fight,' Meadows told Politico of leaving his post in the contentious and divisive Democrat-controlled House.

'So this is not me shrinking away from a fight. In fact, it's just going to be continuing to fight a different capacity, whether that's officially as part of the Trump team or unofficially in my capacity as a sitting member of Congress,' he said.

During the Michael Cohen trial, Meadows had to go on the defensive after a 2012 video surfaced of him talking about sending then-President Barack Obama 'back to Kenya.'

The 2012 video shows Meadows, who was a congressional candidate at the time, saying Obama should be sent 'back home to Kenya or wherever.'

And it surfaced after Meadows' brought an African American administration staffer to Cohen's hearing as proof the president is not racist - a move in itself that one Democrat labeled 'racist.'

President Donald Trump stands with Meadows and then-House Speaker Paul Ryan in 2017

The then-Congressional candidate was speaking at a Tea Party Express Rally at Patton Park in Hendersonville, N.C. on June 9, 2012 - standing on a stage before a bus bearing the label 'Tea Party Express' - when he made his comments.

'2012 is the time we're going to send Mr. Obama home to Kenya or where ever it is. We're going to do it,' Meadows said to great applause.

He won his first term in Congress that year and is now one of President Donald Trump's staunchest allies on Capitol Hill.

The latest administrative decision comes as the Trump administration has faced criticism for its handling of the novel coronavirus outbreak.

Mulvaney had been leading the interagency response to the virus until Trump designated Vice President Mike Pence to lead the whole-of-government effort more than a week ago.

Mulvaney has been marginalized inside the White House for months, taking on a more and more narrow role.

And Trump has been eyeing the change for months, but wanted to wait until after impeachment, according to a person familiar with his thinking who spoke on condition of anonymity because the person was not authorized to discuss it publicly.

Mulvaney's allies, however, had long brushed off rumblings off his imminent departure and had said as recently as last month that he planned to stay at least through the election in November.