Helsinki, Finland (CNN) US President Donald Trump, in a stunning rebuke of the US intelligence community , declined on Monday to endorse the US government's assessment that Russia interfered in the 2016 presidential election, saying he doesn't "see any reason why" Russia would be responsible.

Instead, Trump -- standing alongside Russian President Vladimir Putin -- touted Putin's vigorous denial and pivoted to complaining about the Democratic National Committee's server and missing emails from Hillary Clinton's personal account.

"I have great confidence in my intelligence people, but I will tell you that President Putin was extremely strong and powerful in his denial today," Trump said during a joint news conference after he spent about two hours in a room alone with Putin, save for a pair of interpreters.

Trump's statements amounted to an unprecedented refusal by a US president to believe his own intelligence agencies over the word of a foreign adversary and drew swift condemnation from across the partisan divide.

His words signaled that he continues to equate the assessment of Russian election meddling with efforts to deligitimize his election, even though the US intelligence community made no such assessment.

The US President also hailed Putin's offer for Russian law enforcement officials to interrogate the Russian agents indicted by the special counsel Robert Mueller as "incredible," an offer that would effectively give Russia oversight and influence of part of a US investigation into Russian state activities. Putin had also said the offer would be reciprocal.

Trump repeatedly equated US and Russian actions, saying he holds both the US and Russia responsible for the breakdown in the bilateral relationship and homed in on the effect of the special counsel's probe, saying it -- not Russian meddling -- has "kept us (the US and Russia) apart."

The US intelligence community -- in a report compiled by the CIA, NSA, FBI and the Office of the Director of National Intelligence -- concluded with "high confidence" that Russia interfered during the 2016 presidential campaign, aiming to help elect Trump and hurt Clinton.

Every current US intelligence chief who has testified on the matter has also backed the intelligence community's assessment and the Republican-led Senate Intelligence Committee also affirmed the assessment in a report earlier this month.

Trump had previously said he sided with his intelligence community's assessment over Putin's denials, but he has more frequently cast doubt on the assessments and repeatedly assailed Mueller's investigation as a "witch hunt."

Putin, for his part, reiterated his denial for the public, though he did admit for the first time that he wanted Trump to win the election.

"Russia has never interfered in and is not going to interfere in US internal affairs, including the elections," Putin said during the news conference. "If there are any specific materials, if they are presented, we are ready to review them together."

Trump, aboard Air Force One returning back to Washington, belatedly attempted to quell outrage over his earlier remarks saying he has confidence in his own intelligence officials.

"As I said today and many times before, "I have GREAT confidence in MY intelligence people." However, I also recognize that in order to build a brighter future, we cannot exclusively focus on the past -- as the world's two largest nuclear powers, we must get along!" Trump tweeted.

As I said today and many times before, "I have GREAT confidence in MY intelligence people." However, I also recognize that in order to build a brighter future, we cannot exclusively focus on the past -- as the world's two largest nuclear powers, we must get along! #HELSINKI2018 — Donald J. Trump (@realDonaldTrump) July 16, 2018

But it was his own pick -- Dan Coats, the Director of National Intelligence -- who warned on Friday that "the warning lights are blinking red again" regarding Russian cyber interference. Coats then defended the US intelligence community's assessment about the 2016 election in a statement Monday afternoon.

"We have been clear in our assessments of Russian meddling in the 2016 election and their ongoing, pervasive efforts to undermine our democracy, and we will continue to provide unvarnished and objective intelligence in support of our national security," Coats said.

Democrats and Republicans alike pushed back on Trump's comments.

House Speaker Paul Ryan, who rarely rebukes Trump's controversial statements, said "there is no question that Russia interfered in our elections" and called on Trump to recognize that Russia "is not our ally."

"The President must appreciate that Russia is not our ally. There is no moral equivalence between the United States and Russia, which remains hostile to our most basic values and ideals," Ryan said in a statement.

Other Republicans were even more critical, with Senate Foreign Relations Committee Chairman Bob Corker saying Trump's comments "made us look like a pushover."

John Brennan, the former CIA director and a career intelligence officer, called Trump's comments "nothing short of treasonous."

"Donald Trump's press conference performance in Helsinki rises to & exceeds the threshold of 'high crimes & misdemeanors,' " Brennan tweeted. "It was nothing short of treasonous. Not only were Trump's comments imbecilic, he is wholly in the pocket of Putin. Republican Patriots: Where are you???"

Meeting runs long

Trump and Putin blew past the 90 minutes they were scheduled to spend with only interpreters at their sides on Monday, just hours after the US President blamed US policy for the dismal state of relations between the two countries.

After their initial meeting, the two leaders brought in their top aides for an expanded bilateral meeting, the next step in their first official summit , and then concluded with a joint news conference.

Speaking to reporters, Trump again lambasted the special counsel's investigation stemming from Russian interference in the 2016 election as "a disaster for our country."

"I think that the probe is a disaster for our country. I think it's kept us (the US and Russia) apart. I think it's kept us separated," Trump said.

The US President proclaimed in front of Putin that "there was no collusion" during the 2016 campaign and said he "beat Hillary Clinton easily."

He added the Mueller probe has "had a negative impact on the relationship between the two nuclear powers."

While Trump dove into specifics on US missteps, he did not list any malignant Russian activities responsible for the low point in the US-Russia relationship.

Instead he said he holds both the United States and Russia responsible for the breakdown in the relationship between the two countries and railed against the special counsel's Russia investigation.

"I hold both countries responsible. I think that the United States has been foolish. We've all been foolish," Trump said at the news conference in Helsinki, Finland.

"We should have, frankly, had this dialogue a long time ago. I think that we're all to blame. I think that the United States has now stepped forward along with Russia," Trump said, adding that he feels that the US and Russia have "both made some mistakes."

Historic summit

Gathered at the Finnish presidential palace , a historic venue where previous US presidents have also gathered with their Russian and Soviet counterparts to tackle the complex bilateral relationship, Trump made clear at the outset that he hopes the meeting can help transform the relationship into an "extraordinary" one.

"I think we have great opportunities together as two countries that, frankly, we have not been getting along very well for the last number of years," said Trump, who is hoping his personal touch can reverse the steep decline. "I think we will end up having an extraordinary relationship."

But the highly anticipated meetings that had been minutely planned began with a sluggish start after the Russian President arrived late, setting the summit about 45 minutes back.

Putin is known for arriving late to important events -- considered a power play by some observers -- but this time his late arrival offered a role reversal for the US President, who has recently walked in late to meetings at the G7 and NATO summits.

In 2009 and 2012, Putin showed up about 40 and 45 minutes late for his meetings with then-President Barack Obama. But he kept German Chancellor Angela Merkel and Ukrainian President Viktor Yanukovych waiting about four hours each in 2014 and 2012, respectively. Even the Pope waited more than an hour for Putin to show up at the Vatican in 2015.

The two men walked into the palace's Gothic Hall together, offering brief remarks and shaking hands for the cameras before the two men were left alone -- save for a pair of interpreters -- for the first meeting of the day.

Trump and Putin had set aside 90 minutes of solo time -- just as Trump did with Kim Jong Un last month. But the two men spilled into overtime, inviting reporters for the start of their expanded bilateral meeting with top aides 2 hours and 11 minutes after their one-on-one meeting began. Trump was joined by Secretary of State Mike Pompeo, national security adviser John Bolton, White House chief of staff John Kelly, Fiona Hill, the top Russia expert at the National Security Council, and interpreter Marina Gross.

The lengthy tête-à-tête made Trump's remarks ahead of the meeting all the more notable -- and concerning to some.

Improving US-Russia ties

US officials have stressed the path to improving US-Russia ties runs through a clear-eyed understanding of Russian aggression and the root causes of discord in the relationship, but Trump is signaling a different course. He is holding previous US administrations and the Justice Department's investigation stemming from Russian meddling in the 2016 election responsible.

"Our relationship with Russia has NEVER been worse thanks to many years of U.S. foolishness and stupidity and now, the Rigged Witch Hunt!" Trump tweeted Monday morning ahead of the summit.

Our relationship with Russia has NEVER been worse thanks to many years of U.S. foolishness and stupidity and now, the Rigged Witch Hunt! — Donald J. Trump (@realDonaldTrump) July 16, 2018

Trump was eager to have time alone with Putin to better personally assess him and develop a personal relationship, according to a US official, but he has also expressed anger at leaks from his meetings with foreign leaders and told aides he wanted to ensure his sensitive discussions with Putin remained secret.

The official also said that Trump doesn't want aides -- who may take a harder line on Russia -- undercutting or interrupting him during his talks with Putin.

Just days earlier, Trump pointed to the "pure stupidity" and a "political problem" in the United States for making it "very hard to do something with Russia."

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"Anything you do, it's always going to be, 'Oh, Russia, he loves Russia,' " Trump said during a joint news conference with his British counterpart.

Ahead of his meeting with Putin -- who is alleged to be behind the assassination of journalists and political dissidents -- the US President also lashed out again at the news media on Sunday by branding journalists "the enemy of the people."