Defense Secretary Jim Mattis on Friday called NBC News’ report that said the Pentagon was in “damage-control” mode to reassure NATO allies after President Trump’s visit “fiction.”

Mattis, during a press gaggle on the way to Oslo, Norway, brought up the report, which claimed that “hours” after Trump departed NATO, U.S. military leaders embarked on a “full-scale” damage-control operation across Europe.

The report said U.S. military leaders were “directed by the Pentagon leadership” in response to Trump threatening to reassess U.S. commitments in the region.

“That was fascinating. I love reading fiction, so it was stimulating to read it,” he said sarcastically. “I find out that while I’ve been with you in full transparency on the airplane with you watching what’s going on that I’ve been in damage control.”

“It must have been the most pleasant damage control [I] ever could have imagined with the level of unity of purpose that we experienced there. So anyway, people are entitled to their own opinion, even if it’s not facts-based,” he added.

NBC News has also reported recently that Mattis was increasingly “isolated” within the White House. Shortly afterward, Mattis said he was working closely with Secretary of State Mike Pompeo, and had lunch with the president at least twice before going with him to the summit.

The recent NATO summit put focus on the Pentagon, which has a large role in maintaining the transatlantic military alliance.

During the recent summit for NATO member heads of state, Trump lambasted members for not meeting an agreed-upon benchmark of spending at least two percent of their gross domestic product on their own defense. Only four members currently meet that mark, although four more are expected to this year. But only 16 have a plan to reach that goal by 2024.

The Washington Post reported ahead of the NATO summit that Trump had expressed interest in removing troops from Germany, and that the Pentagon was reassessing the cost of stationing U.S. troops in Germany.

The Pentagon said those cost assessments happen across the globe and are constant, and the White House has not actually asked for any such assessments.