Former Trump campaign manager Corey Lewandowski on Sunday acknowledged tensions with White House Chief of Staff John F. Kelly but disputed that the Secret Service once had to break up a fight between the two earlier this year.

“Well, the Secret Service didn’t break anything up. John and I had a very candid discussion, as he probably has many times with the president,” Lewandowski said in an appearance on “Fox News Sunday.”

Lewandowski and David N. Bossie, Trump’s former deputy campaign manager, were on the show to promote their new book, “Trump’s Enemies,” in which they allege that scores of administration officials are actively working against the president’s agenda.

Lewandowski acknowledged that he and Kelly have “very different management styles.” But asked by Fox News host Chris Wallace whether Kelly had grabbed him during the February altercation, as the New York Times reported last month, Lewandowski declined to say.

“Look, I don’t want to get into what John may or may not have done,” he said. “But what I do think is he understands that my position is to support the president and the president’s agenda all the time.”

Tensions between the two erupted into a “near brawl” in February during which Kelly grabbed Lewandowski by the collar and sought to have him removed from the West Wing, the Times reported. Lewandowski did not get physical in return, according to the report, but Secret Service agents were called in to de-escalate the situation.