Standing alongside Putin at the news conference in Helsinki on Monday, Mr Trump was asked if he believed USA intelligence agencies' conclusions that Russian Federation interfered in the election in an effort to help him defeat Democrat Hillary Clinton.
At the press conference, which followed an hourslong private meeting between Trump and Putin, Trump cast doubt on the USA intelligence community's assessment that Russian Federation interfered in the 2016 United States presidential election.
Putin also suggested Monday that Moscow and Washington could jointly conduct criminal investigations into a dozen Russian intelligence officials accused of hacking during the 2016 US election campaign - an idea Trump hailed as an "incredible offer".
In Finland, which played host to the summit, newspaper Kauppalehti used a soccer analogy in its headline: "Trump 0-1 Putin", along with a photo of Trump holding a soccer ball given to him by the Russian leader.
The Russian foreign ministry responded by liking Trump's tweet and then replying: "We agree".
Cody Fenwick is a reporter and editor.
He disembarked his official jet before climbing into a newly commissioned Aurus Senat limousine and riding off in a motorcade similar to the one that accompanies president Trump.
On Tuesday, after he arrived back in the US, Trump told reporters at the White House that he misspoke at the summit.
"Would you now, with the whole world watching, tell President Putin, would you denounce what happened in 2016, and would you warn him to never do it again?"
Senior members of Mr Trump's Republican party have also rebuked him over his refusal to call out Mr Putin for interfering in USA elections. After his electoral victory, which caught even Trump by surprise, the president reluctantly acknowledged Russian meddling in the election - the unanimous consensus of the intelligence community - while in the same breath suggesting other countries could be responsible.
Senator Rand Paul of Kentucky was one of the few Republican colleagues of Trump who came to his defense, saying, "The President has gone through a year and a half of totally partisan investigations - what's he supposed to think?" "However low your expectations were, Trump managed to go much lower", he said.
Former Director of National Intelligence James Clapper, who served during the Obama administration, said it was 'truly unbelievable'.
"The cover story to accompany the cartoon is titled 'Putin's Poodle: Trump sells out USA intelligence agencies with the world watching". I will say this: "I don't see any reason why it would be", Trump said.
President Donald Trump lives in a world in which he "had a great meeting with NATO" and "an even better meeting with Vladimir Putin of Russian Federation". Lemire asked Mr Trump. "There is no moral equivalence between the United States and Russian Federation, which remains hostile to our most basic values and ideals".
The host also mocked Trump for blaming both the United States and Russian Federation for the break down in the relationship between the two countries.
Team Trump has denied allegations that they were in any way connected to the alleged hacking or interference.
Former intelligence chief, James Clapper, called Trump's acquiescence to Putin "an incredible capitulation", while former CIA chief John Brennan labelled it "nothing short of treasonous".