THE HAGUE, Netherlands — President Donald Trump on Wednesday rejected an early intelligence assessment that U.S. strikes inflicted only a marginal setback on Iran’s nuclear program, insisting that his country’s spies did not have the full picture and defending his own swift conclusion that American bombs and missiles delivered a crushing blow.

“This was a devastating attack, and it knocked them for a loop,” Trump said as his administration scrambled to support his claims, made only hours after the attack, that Iranian nuclear facilities were “completely and fully obliterated.”

Trump said Defense Secretary Pete Hegseth and other military officials would hold an “interesting and irrefutable” news conference Thursday morning to “fight for the Dignity of our Great American Pilots” who carried out the mission.

He wrote on social media that “these Patriots were very upset” by “Fake News” reports about the limited impact of the strikes.

The issue dominated Trump’s attendance at NATO’s annual summit in the Netherlands, which was otherwise focused on European security. The White House highlighted an Israeli statement that Iran’s nuclear efforts were delayed by years, much longer than the few months determined by American intelligence. A spokesperson for the Iranian foreign ministry also said the facilities have suffered significant damage.

But those comments fell short of Trump’s hyperbole and did little to suggest that U.S. strikes had eliminated the threat of Iran developing a nuclear weapon.

Secretary of State Marco Rubio, speaking in an interview with Politico, limited his own assessment to saying Iran was “much further away from a nuclear weapon today than they were before the president took this bold action.”

Drawing reliable conclusions about the impact of the U.S. strikes remains difficult, especially only days after they took place. That makes the issue a breeding ground for competing claims that could determine how American voters view Trump’s risky decision to join Israel’s attacks on Iran.

Jeffrey Lewis, a professor of nonproliferation at the Middlebury Institute, said Trump was trying to have it both ways.

“If it’s too early to know, why is Trump saying it’s obliterated?” he said. “Either it’s too early to know, or you know.”

Also at stake are Trump’s next steps in the Middle East, where diplomatic efforts could be required to prevent Iran from rebuilding its nuclear program.

Trump said U.S. and Iranian officials would meet soon, resuming a dialogue that was interrupted by nearly two weeks of war, even as he suggested that negotiations were no longer necessary.