Former White House Chief of Staff John Kelly was overheard in the West Wing in a conversation with former Deputy White House Chief of Staff Joe Hagin deliberately undermining President Donald Trump’s strategy on Syria, an excerpt from a forthcoming book from a former White House official provided exclusively to Breitbart News alleges.

Former West Wing communications official Cliff Sims, the author of Team of Vipers: My Extraordinary 500 Days in the Trump White House, describes in the book how he heard Kelly in conversation with Hagin about how to stop Trump from withdrawing U.S. forces from Syria–a point of contention between Trump and Kelly.

Sims describes the hallway between the Oval Office and the Vice President’s suite in the West Wing, setting the scene for what he heard Kelly saying about Trump’s policies:

On the afternoon of Thursday, March 29, I was sitting in the back hall­ way of the West Wing, outside Jared’s office, waiting to fill him in on my impending move to the NEC. The President was in Richfield, Ohio, announc­ing plans to “rebuild America’s crumbling infrastructure,” so in his absence, the West Wing was uncharacteristically quiet. But since he was flying straight from Ohio to Mar­-a­-Lago for a long Easter weekend, most of the staff had stayed behind, including General Kelly and Deputy Chief of Staff Joe Hagin. The back hallway of the West Wing is a roughly twenty­-five­-yard straight shot from the Oval on one end to the Vice President’s suite on the other. Work­ing your way down the hallway from the Oval, on the left side was the Pres­ident’s private dining room, Jared’s office, then the Chief’s suite. On the right side were the Roosevelt Room; the scheduler, Michael Haidet; and Hagin. This was the most prime real estate in the entire building. In an environment where proximity to the President was power, this was the inner sanctum. The hallway was lined with the usual combination of historical paintings, an­tique cabinetry, and famous busts and sculptures. The ceiling was slightly curved, like the top of the number zero. While the upper press office, where I worked, was the bustling center of activity, not to mention accessible to the media, this place was almost serene. About fifteen feet down the hallway from where I was sitting, I could hear the TV inside the Chief’s suite airing coverage from Trump’s Ohio event, which was set to begin any minute. Hagin sauntered out of his office and across the hall, where he found Kelly standing in front of the TV with a couple of other close aides. Though I hadn’t intended to, I overheard their entire, un­ guarded conversation.

At that point, Sims then describes the conversation he overheard between Kelly and Hagin, in which they criticized the president’s style of rolling out major announcements–and where Kelly said that Trump “better not” announce a U.S. withdrawal from Syria:

“I talked to the President on the plane and he swore to me that he wouldn’t announce anything about Syria,” Kelly said, in an exasperated tone. I knew immediately what he was talking about. The President had for some time been privately expressing a desire to pull U.S. troops out of Syria. I wasn’t involved in the national security decision­-making process, but his inclination to pull out was well known throughout the building. Top military officials were urg­ing him to keep a couple of thousand troops in the country to clear out the last remnants of the so-called Islamic State. To that point he had begrudg­ingly acquiesced, but his patience was running thin. Kelly clearly was expect­ ing him to say something about the topic anyway. “We won’t know until he walks offstage,” Hagin replied with a resigned chuckle. This was a common sentiment among staffers who bristled at Trump’s tendency to go off script during his remarks. It also happened to be what made him interesting to watch—no one knew what he would say, not even the staff. “He d— well better know not to screw us on this,” Kelly growled. I was taken aback by this brief but revealing exchange, which seemed to encapsu­late Kelly’s view of his job and of the President himself: which was that Trump was a missile of chaos and Kelly was the general trying to keep him in the silo. Many reporters over the years reported that this was Kelly’s view of the job—to various denials from the White House—but we all knew it was true.

Later in the year and after the midterm elections, the president would announce the withdrawal from Syria despite opposition from Kelly and other military officials.

At the end of this excerpt, Sims describes the attitude of Kelly and others who viewed it as their mission to stop Trump from doing what he set out to do as president:

In fact, there was a pervasive view among some of the President’s most senior aides that there was something patriotic about undermining Trump’s most disruptive impulses. I know that many people reading this will say, “Thank God.” And if I give them the benefit of the doubt, it may have been a sincere effort to do what they thought was in the best interest of the coun­try. But whether they were sincere or not, I found it cowardly. There’s noth­ing patriotic about being a part of “the resistance” inside the building. Imagine the arrogance of saying, “I know sixty­ three million of my fellow Ameri­cans voted for this guy, but I’m going to sabotage him anyway because I know better.”

This is hardly the only excerpt regarding Kelly in Sims’ explosive book, which has already seen stories come out about how Sims recounts the creation in a secret meeting with Trump of an enemies list of people Trump could not trust and a separate list of those he could trust. Sims, unlike many others who have left the White House and gone on to attack the president in books or public comments, remains loyal to Trump and is trying to out leakers–or sleeper cells, as they are called–in the West Wing. One alleged leaker exposed in another excerpt in Sims’ book is White House counselor KellyAnne Conway, who, Sims recounts in an excerpt published by Vanity Fair, asked him to write a statement on her computer saying she was not disloyal or leaking–while he watched messages appear on her screen between her and media figures in which she allegedly trashed the president, his family, and his administration.

The other Kelly excerpt in Sims’ forthcoming book recounts Kelly’s first day as White House chief of staff, and a speech he gave to the entire staff of the White House, including the broader campus which includes hundreds of officials who do not work regularly in the West Wing.

Sims recounts how he thought Kelly’s speech started strong, and he thought he might actually become an ally of the president’s agenda in the White House:

Kelly assembled all of the staff working in the EEOB to deliver his introductory remarks. He stood at a podium at the intersection of two large hallways, black­-and-­white-­checkered floors stretching the length of a city block. Several hundred staffers crowded around him. Some of us from the West Wing walked across the driveway as well, curious to hear what he would say. “Nice to meet you, I’m from Boston,” he said right off the bat. I smirked and nodded my head. We were from dramatically different places, but I was proud of where I came from, too. I felt like it said something about who I was. Kelly clearly felt the same way about his blue­-collar roots. I liked that about him right away.

Sims’ positive impressions did not last long. He continues:

But then things got a little weird. The primary theme of his speech was that he planned to approach his new job by serving the country, then the President, in that order, and that we should do the same. At first blush, this didn’t seem like a particularly profound state­ment, much less a controversial one. But the more he spoke, the more he seemed to really be hammering on this construct: country, then President, country, then President. And the more I let it soak in, the more I thought that what Kelly was saying—country first, POTUS second—was, at best, a bit curious, and at worst, potentially hostile.

We believed that the way we served our country was by serving the Pres­ident. Kelly, on the other hand, seemed to be intimating that those two goals might be at odds, perhaps even mutually exclusive at times. And you know what? Maybe they would be. But if they ever were, the honorable response would be to resign. Maybe we were being paranoid after being in the Trump bunker for so long, but Kelly seemed to be saying that, in such a scenario, it might be necessary to subvert the President’s wishes in service of some amor­phous higher calling. Most of us had met his arrival with optimism after enduring six months of staff upheaval. Now I was watching some of the President’s most ardent supporters shuffling back to their offices, hanging their heads in concern. “What a letdown,” one of them said. “He comes across like he doesn’t even like the President, much less want to work for him.” I am still not certain what motivated Kelly to use his first interaction with the majority of the White House staff to say what he did… But right off the bat his remarks hurt his stand­ing among loyal aides who were hoping he could unify the fractious staff behind a singular mission: advancing the President’s agenda.

This week, Kelly signed onto a letter with other anti-Trump forces pushing the President to end the shutdown without a border wall. This is powerful evidence supporting Sims’ claims Kelly had wanted to subvert the President’s agenda.

Kelly, who served as Secretary of Homeland Security before taking the chief of staff position in the White House, signed a letter with other former Secretaries of Homeland Security calling on Trump to cave on the government shutdown and reopen the government without a border wall.

JUST IN: 5 former DHS secretaries, including former Trump Chief of Staff John Kelly, call for President Trump and Congress to "fund the critical mission of DHS," according to letter obtained by @NBCNews – @jesserodriguez https://t.co/whd8qQSFCW pic.twitter.com/UBwYqYPQYT — NBC News (@NBCNews) January 24, 2019

In addition to Kelly, the letter was signed by former George W. Bush DHS Secretaries Michael Chertoff and Tom Ridge, as well as Barack Obama DHS secretaries Janet Napolitano and Jeh Johnson.