EXCLUSIVE: 'Throw him out of MY building.' Trump's former campaign manager Corey Lewandowski tells how the rivalry between him and John Kelly exploded when the White House chief of staff threw him against a wall outside the Oval Office in new book

Corey Lewandowski, Donald Trump's campaign manager for the 2016 presidential election and current senior adviser to the 2020 campaign,  and political activist David Bossie, Trump's former deputy campaign manager, have shared an excerpt of their new book Trump: America First exclusively with DailyMail.com readers.

Corey Lewandowski, Donald Trump's campaign manager for the 2016 presidential election and current senior adviser to the 2020 campaign,  and political activist David Bossie, Trump's former deputy campaign manager, have shared an excerpt of their new book Trump: America First exclusively with DailyMail.com readers.

The close advisors to the president share their accounts of their time with Trump from 'the front lines of his battle to keep America great' and inside 'the rough-and-tumble world of Trump's West Wing'.

The close advisors to the president share their accounts of their time with Trump from 'the front lines of his battle to keep America great' and inside 'the rough-and-tumble world of Trump's West Wing'.

A passage of the book includes details of how Lewandowski nearly came to blows with Trump's former White House Chief of Staff John Kelly outside the Oval Office - until Lewandowski brought up Rob Porter. 

Porter, who was dating Hope Hicks, would eventually resign from his position as White House Staff Secretary after DailyMail.com revealed accusations of domestic violence from his two ex wives. 

Around noon on February 21, 2018, Corey Lewandowski was sitting in a restaurant near the White House. He was having a cup of coffee with then White House communications director Hope Hicks, whom he had known since the earliest days of the 2016 campaign. 

Corey was initially supposed to meet Hope at the White House mess located in the basement of the West Wing. That had been the plan, at least, until John Kelly stepped in. 

Earlier that morning, Hope called Corey to let him know that the White House chief of staff had restricted his access to the building.

Corey Lewandowski and political activist David Bossie, Trump's former deputy campaign manager, have shared an exclusive excerpt of their new book Trump: America First exclusively with DailyMail.com. A passage of the book includes details of how Lewandowski nearly comes to blows with Trump's former White House Chief of Staff John Kelly outside the Oval Office

Lewandowski claims that 'gate-keeper' Kelly was annoyed by his close relationship with President Trump and restricted his access to the White House 'From now on, if you want to come into the White House, you have to call me first,' Kelly told Lewandowski in an exasperated tone

Lewandowski claims that 'gate-keeper' Kelly was annoyed by his close relationship with President Trump and restricted his access to the White House 'From now on, if you want to come into the White House, you have to call me first,' Kelly told Lewandowski in an exasperated tone

Kelly, as you might remember, made it his mission to wall the president off from any outside influences, including friends and trusted advisors like us. 

He was supposed to be 'the adult in the room,' remember? We all know how that worked out. Last we heard, he was getting booed off the stage at some paid speech in New Jersey.

In the middle of his meeting with Hope, Corey's phone rang. It was Zach Fuentes, John Kelly's deputy, asking Corey if he would be available that afternoon to meet with the chief of staff. 

After being informed his access to the White House had been restricted, Corey was more than happy to have the chance to speak to Kelly one-on-one.

Corey Lewandowski and political activist David Bossie, Trump's former deputy campaign manager, will have their new book released on Tuesday

Corey Lewandowski and political activist David Bossie, Trump's former deputy campaign manager, will have their new book released on Tuesday 

At 4.30pm, Corey was seated at the large conference table at the far side of the chief of staff's office. Before Kelly even entered the room, Corey could feel the hostility. 

Initially, he thought General Kelly wanted to speak with him about a recently publicized meeting that had taken place in the Oval Office a few months back. 

At that meeting, which included White House political director Bill Stepien, counselor to the president Kellyanne Conway, 2020 campaign manager Brad Parscale, Hope Hicks, and John Kelly, Corey excoriated the White House's political operation. 

He told them they were woefully behind where they should be and weren't ready for what was to come in the midterm elections. Corey had rightly predicted that a Democrat wave was about to crash over the House of Representatives. 

Combined with the mass exodus of Republican retirements from Congress, the caucus would be a shadow of its former self. 

There was no way it would be able to protect the president, let alone help him advance his 'America First' agenda. Once the Republicans lost the House, Corey told them, impeachment wouldn't be far behind.

Though his predictions were spot on, his analysis didn't make him any friends that day. 

The chief of staff, however, wasn't concerned with that meeting in the Oval Office. What bothered John Kelly was Corey's close relationship with President Trump.

'From now on, if you want to come into the White House, you have to call me first,' he said in an exasperated tone.

'That's bulls**t,' Corey said to himself, but he didn't show his emotions to General Kelly. He mentioned something to the effect of it not being a good use of his time— because it wasn't. 

The close advisors to the president share their accounts of their time with Trump from 'the front lines of his battle to keep America great' and inside 'the rough-and-tumble world of Trump's West Wing'The close advisors to the president share their accounts of their time with Trump from 'the front lines of his battle to keep America great' and inside 'the rough-and-tumble world of Trump's West Wing'

Lewandowski and Bossie share their accounts of their time with Trump from 'the front lines of his battle to keep America great' and inside 'the rough-and-tumble world of Trump's West Wing'

With all that the White House chief had to do, it seemed crazy to Corey that John was going to try to be some sort of gatekeeper as well. 

But Corey knew it would be the wrong move to engage John while he seemed so angry. It wasn't the appropriate time or place . . . for now. 

Corey tried to ease the tension by reminding the general that they both had the same goal: making sure the president is successful.

'Don't kid yourself,' Kelly said, 'My goal is to save my country.'

If you've ever had a moment when, all at once, your opinion changed, you'll understand how Corey felt. 

Here was the White House chief of staff telling him that he didn't care if the president of the United States was successful—that he didn't care if the president delivered for the American people or not. 

Though shocking, Kelly's words weren't all that big of a surprise. Kelly had no qualms about showing his allegiance to the Deep State. 

According to media reports, after the president fired FBI Director James Comey in May 2017, Kelly called the disgraced head of the FBI and apologized for the president.

Then he said he would resign from his post as secretary of homeland security if the director wanted him to. The general, it seemed, had different priorities from those of his commander in chief.

If there had been tension in the room before, Kelly's affirmation of indifference pushed it to the next level. Just then, however, Kelly's phone rang; the president wanted to see him in the Oval Office. Tension diffused—for now.

As they passed each other in front of the Resolute Desk, Kelly said to Corey under his breath, 'F**king a**hole.' When Corey asked him what his problem was, Kelly started ranting about Corey 'getting rich' off the Trump super PAC. Kelly didn't appreciate that the president had defended Corey right in front of him, without even thinking twice. Pictured: Trump on February 21, 2018

As they passed each other in front of the Resolute Desk, Kelly said to Corey under his breath, 'F**king a**hole.' When Corey asked him what his problem was, Kelly started ranting about Corey 'getting rich' off the Trump super PAC. Kelly didn't appreciate that the president had defended Corey right in front of him, without even thinking twice. Pictured: Trump on February 21, 2018

Corey left the office and walked upstairs to visit his old campaign colleague Don McGahn, then the White House counsel, before coming back down to say hello to Dan Scavino, whose office is located just outside the Oval Office. 

But on his way to see Dan, he noticed that the door to the Oval Office was open. 

Madeleine Westerhout, at the time the president's personal assistant, told him that the president was free to see him if he would like. As Corey walked in, Kelly began to walk out. 

As they passed each other in front of the Resolute Desk, Kelly said to Corey under his breath, 'F**king a**hole.' When Corey asked him what his problem was, Kelly started ranting about Corey 'getting rich' off the Trump super PAC.

Getting rich? If anything, Corey was leaking money. He'd already run up a few hundred thousand dollars in fees fighting off the phony Mueller investigation just for being loyal to the president.

The president looked at Kelly and shook his head slowly. 'What's wrong with you, John? Corey isn't getting rich,' he said, referring to Corey's $10,000-a-month salary from the super PAC. 

Kelly didn't appreciate that; as a matter of fact, it only enraged him further. The president had defended Corey right in front of him, without even thinking twice. 

John stormed out of the Oval Office but stalked Corey in the outer Oval, lurking angrily like a petulant child. As Corey and the president began to talk, Madeleine informed the president he had a phone call. It was Christopher Wray, the FBI director.

Porter, who was dating Hope Hicks, would eventually resign from his position as White House Staff Secretary after DailyMail.com revealed accusations of domestic violence from his two ex wives. Pictured: Porter and Hicks in November 2017

Porter, who was dating Hope Hicks, would eventually resign from his position as White House Staff Secretary after DailyMail.com revealed accusations of domestic violence from his two ex wives. Pictured: Porter and Hicks in November 2017

Corey respectfully excused himself to give the president privacy, and as he stepped out of the Oval Office, he heard Kelly say to someone out of his sight, 'When he gets out of there, throw him out of my f**king building.'

'Hey, John,' Corey said, 'last I checked this, isn't your building. It's the White House.' Tension exploded.

Kelly turned and came running back into the outer Oval Office with his Secret Service protection in tow. 

He grabbed Corey with both hands and pushed him up against the Oval Office's outside wall. 

While pushing his hands away, Corey told him to get his f**king hands off of him or he'd call the DC police and have him arrested for assault.

'Or we can just go outside and finish it out there,' Corey said. 'Up to you, John.' Corey grew up in Lowell, Massachusetts. Going 'outside' with someone was his default setting.

Corey pointed to Hope's unoccupied office—an alternative option after Kelly's expression said all it needed to in rejecting his offer to step outside. 

Kelly followed Corey through the open door, and as he closed the door behind him, Corey reminded him that he was in no position to make accusations.

'What are you talking about?' John barked.

'Two words,' Corey said. 'Rob Porter.'

EDITOR'S NOTE: Lewandowski was referring to Kelly’s vociferous defense of White House staffer Rob Porter and the fact that the chief of staff had been aware of the alleged spousal abuse all along.