President Trump on Sunday sought to move past allegations of Russian interference in the 2016 U.S. election, effectively dismissing the importance of the intelligence community’s definitive conclusion about a foreign adversary, in pursuit of a collaborative partnership with Russian President Vladimir Putin.

Issuing his first public comments since sitting down with Putin in Germany, Trump vowed to “move forward in working constructively with Russia,” and said the two leaders were forming a cybersecurity unit to protect against the kinds of illegal intrusions that U.S. intelligence agencies say Putin ordered in the United States.

After Putin denied any such election interference in his meeting with Trump, the president tried to turn the page altogether on the issue of Russian hacking. As Special Counsel Robert S. Mueller III investigates Russian interference and possible collusion with Trump campaign officials, Trump has repeatedly labeled the issue a “hoax” and portrayed it as a dark cloud unfairly hanging over his first six months as president.

Trump’s pledge to partner with Putin drew swift and stern denunciations from both Democratic and Republican officials, who cast the president as dangerously naive for trusting his Russian counterpart and said Russia must be forced to pay a price for its election interference.

Trump said he “strongly pressed” Putin twice about Russian meddling and that Putin “vehemently denied it.” Trump did not say whether he accepted Putin’s denial, saying only, “I’ve already given my opinion.”

Trump delivered his account of the meeting with Putin, held Friday on the sidelines of the Group of 20 summit in Hamburg, via a series of defiant tweets fired off Sunday morning from the White House, just before visiting his Northern Virginia golf course – as opposed to a news conference like the one Putin held with journalists Saturday.

Putin, as well as Russian Foreign Minister Sergey Lavrov, said that Trump believed Putin’s assurances that Russia did not interfere in the election.

“It seemed to me that he took it into account, and agreed,” Putin told reporters Saturday, though he added, “you should ask him.”

Initially, U.S. officials traveling with Trump would not dispute Putin and Lavrov’s accounts when asked by reporters. On Sunday, however, White House chief of staff Reince Priebus, who remained in Washington during the trip, rejected the Russian characterization.

“It’s not true,” Priebus said on “Fox News Sunday.” “The president absolutely did not believe the denial of President Putin.”

U.S. intelligence agencies have concluded definitively that Russian authorities tried to influence the election in Trump’s favor with illegal hacking and propaganda and other activities.

Trump’s public comments on the issue have been far less definitive, varying widely from tepid acknowledgment to outright doubt about Russia’s role. Under questioning from Fox host Chris Wallace, Priebus also showed varying degrees of certainty about whether Trump believes Russia meddled in the election.

“He said they probably meddled in the election. They did meddle in the election,” Priebus said, seeming to grow more definitive.

But then he seemed to back off: “Yes, he believes that Russia probably committed all of these acts that we’ve been told of. But he also believes that other countries also participated in this activity.”

Trump on Sunday revealed his continued fixation with some aspects of the Russia issue. He falsely accused President Obama of doing “NOTHING” after learning of the Russian hacking before the election.

In fact, on Oct. 7, about a month before the election, the Obama administration formally and publicly blamed Russia for the hacking, though some Obama administration officials have since said they regret not responding more forcefully.

Trump also chided the news media and, in the context of his meeting with Putin, claimed vaguely that “questions were asked” about the level of cooperation between intelligence agencies and the Democratic National Committee, whose email server was among those allegedly compromised by the Russians.

John Brennan, who served as CIA director under Obama and ran the agency’s response to Russia’s election interference, chastised Trump on Sunday for repeatedly casting doubt on the conclusions of the intelligence community, including at a news conference last week in Poland.

“I seriously question whether or not Mr. Putin heard from Mr. Trump what he needed to about the assault on our democratic institutions,” Brennan said on NBC’s “Meet the Press.”

Brennan added of Trump, “He said it’s an ‘honor’ to meet President Putin. An honor to meet the individual who carried out the assault against our election? To me, it was a dishonorable thing to say.”

Sens. John McCain, Ariz., Lindsey Graham, S.C., and Marco Rubio, Fla. – three leading Republican hawks on Russia – said Sunday that Trump’s eagerness to partner with Putin was dangerous for the United States.

“When it comes to Russia, he’s got a blind spot,” Graham said on NBC’s “Meet the Press.”

“To forgive and forget when it comes to Putin regarding cyberattacks is to empower Putin, and that’s exactly what he’s doing,” Graham said.

Rubio tweeted that Putin “will never be a trusted ally or a reliable constructive partner,” and that working with him to address cybersecurity threats was akin to partnering with Syrian President Bashar al-Assad to protect against chemical weapons.

McCain, meanwhile, lamented that Russia has faced “no penalty whatsoever” from the Trump administration for its hacking.

“We know that Russia tried to change the outcome of our election last November, and they did not succeed, but there was really sophisticated attempts to do so,” McCain said on CBS’s “Face the Nation.” “So far, they have not paid a single price for that.”

Invoking the language of Trump’s tweet, McCain added, “Yes, it’s time to move forward, but there has to be a price to pay.”

McCain championed a bill, passed overwhelmingly in the Senate last month, to slap additional sanctions on Russia.

The Trump administration has said it opposes the measure because it preempts the president’s powers to apply sanctions.

Nikki Haley, the U.S. ambassador to the United Nations, defended her boss’ cooperation with Putin, saying that “we won’t ever trust Russia” but that working with Russia on cybersecurity will “keep them in check.”

“From a cyber standpoint, we need to get together with Russia, we need to tell them what we think should happen, shouldn’t happen, and if we talk to them about it, hopefully, we can cut this out and get them to stop,” Haley said Sunday on CNN’s “State of the Union.”

She continued: “It doesn’t mean we’ve ever taken our eyes off of the ball. It doesn’t mean we ever trust Russia. We can’t trust Russia and we won’t ever trust Russia. But you keep those that you don’t trust closer, so that you can always keep an eye on them and keep them in check, and I think that’s what we’re trying to do with Russia right now.”