President Donald J. Trump reacted on Monday to the news that an informant was reporting to the FBI about his campaign.

“If they had spies in my campaign that would be a disgrace to this country. That would be one of the biggest insults that anyone has ever seen, and it would very illegal,” Trump said. “It would make every political event ever look like small potatoes … I hope they weren’t, frankly.”

The president commented on the news during his meeting with South Korean president Moon Jae-in at the Oval Office.

Trump said that his meeting with Justice Department officials on Monday was a “routine meeting” where they discussed the Congressional requests for information about the case. “As you know, the Congress would like to see documents opened up,” he said. “A lot of people are saying they had spies in my campaign.” Trump said that White House chief of staff General John Kelly was setting up a meeting between members of Congress and Justice Department officials to share intelligence.

But he again stressed that the notion of spying on a political campaign would be “unprecedented in the history of this country.”

The informant, Cambridge University professor Stefan Halper, met with officials in the Trump campaign in 2016, reporting details of his conversations to the FBI.

“That is not a normal situation,” Trump said, pointing to the reported payments that Halper received from the government.

When asked if he had confidence in United States Deputy Attorney General Rod Rosenstein, Trump replied sharply.

“Next question,” he said and added, “Excuse me. I have the president of South Korea here. He doesn’t want to hear these questions if you don’t mind.”