President Donald Trump lashed out at Democrats on Friday, slamming them for "rooting against" him on North Korea and accusing the opposition party of not being outraged over his claims that there had been a "spy" in his campaign.

The Twitter tirade came a day after Trump suddenly canceled a summit with North Korean leader Kim Jong Un that had been scheduled for June 12 and after the Justice Department briefed a group of top lawmakers about the FBI's investigation into Trump's 2016 campaign.

The Democrats are now alluding to the the concept that having an Informant placed in an opposing party’s campaign is different than having a Spy, as illegal as that may be. But what about an “Informant” who is paid a fortune and who “sets up” way earlier than the Russian Hoax? — Donald J. Trump (@realDonaldTrump) May 25, 2018

Can anyone even imagine having Spies placed in a competing campaign, by the people and party in absolute power, for the sole purpose of political advantage and gain? And to think that the party in question, even with the expenditure of far more money, LOST! — Donald J. Trump (@realDonaldTrump) May 25, 2018

“Everyone knows there was a Spy, and in fact the people who were involved in the Spying are admitting that there was a Spy...Widespread Spying involving multiple people.” Mollie Hemingway, The Federalist Senior Editor But the corrupt Mainstream Media hates this monster story! — Donald J. Trump (@realDonaldTrump) May 25, 2018

Democrats are so obviously rooting against us in our negotiations with North Korea. Just like they are coming to the defense of MS 13 thugs, saying that they are individuals & must be nurtured, or asking to end your big Tax Cuts & raise your taxes instead. Dems have lost touch! — Donald J. Trump (@realDonaldTrump) May 25, 2018

Congressional Democrats had said that the classified briefing held Thursday did not offer evidence that supports the allegation that an intelligence agency placed a spy in the campaign, as Trump has repeatedly claimed.

"Nothing we heard today has changed our view that there is no evidence to support any allegation that the FBI or any intel agency placed a spy in the Trump campaign," Rep. Adam Schiff, D-Calif., told reporters, reading from a statement from himself and three other Democrats: House Minority Leader Nancy Pelosi of California, Senate Minority Leader Chuck Schumer of New York and Sen. Mark Warner of Virginia.

With increasing frequency and venom, Trump has been ramping up his attacks in recent days on the FBI's reported use of an informant to investigate his campaign, dubbing it "Spygate" and slamming it as "one of the biggest political scandals in history."

After Trump announced Thursday that he had canceled the summit with Kim, Democrats said the president got played.

"Kim Jong Un is the big winner," Pelosi said.

Sen. Bob Menendez, D-N.J., the ranking member of the Senate Foreign Relations Committee, criticized the administration for an alleged lack of preparation for the now-canceled summit.

Earlier Thursday, in a letter addressed to Kim and released by the White House, Trump blamed the cancellation on the "tremendous anger and open hostility" in a recent statement by the North Koreans. That appeared to be a reference to a statement by North Korea on Thursday that warned of a "nuclear-to-nuclear showdown" with the United States.