But even as Trump said he accepted US intelligence agencies' conclusions that Russian Federation was behind the election hacking, he added, as he has before: "It could be other people also. There was no collusion at all".
Several Republicans said they would consider new legislation to sanction Russian Federation for future election meddling, after Trump declined an opportunity to publicly warn Putin against such interference.
But on Tuesday, Trump claimed that he misspoke, explaining that he meant to say that he saw no reason why it would not be Russian Federation.
"I said the word "would" instead of 'wouldn't, '" said Trump, according to NBC News.
But, as he has done before, Trump added: "Could be other people also; there's a lot of people out there".
But tonight, Trump has dramatically rowed back on his comments, insisting that he meant to say he "did" believe Russian Federation was involved in attempting to influence the outcome of the vote.
"Loyalty right now requires you to tell the truth and sit with him and explain to him the optics of the situation, why the optics are bad, the strategy in terms of trying to get along with Vladimir Putin and deploying a strategy of going against the intelligence agency is very bad", Scaramucci said.
Today's clarification from Mr Trump comes amid an ongoing investigation into possible collusion between his campaign and Russian Federation during the 2016 election.
The White House announced later in the day that President Trump would defend his Helsinki summit directly to cameras in an effort to blunt criticism.
He reiterated his long-held stance that Russia's meddling operation did not change the outcome of his win over Democratic nominee Hillary Clinton, and again said he believes other entities - not just Russian Federation - tried to upend the 2016 race.
The officials said it became clear early Tuesday that initial discussions of clarifying his remarks on Twitter would not prove sufficient, as Trump was hearing from more and more people through phone calls and messages that he had to say something.
Trump still maintained that his meetings with North Atlantic Treaty Organisation allies went well and his summit with Putin "even better". "I want [allies] to understand that, in this country, there are lot people in both parties who believe that these alliances painstakingly built in the wake of the end of World War II are important and we want to maintain them". Kentucky Sen. Rand Paul emerged as one of the president's few defenders from his own party.
Trump, the first lady, Shine and Miller were seen in animated conversation aboard Marine One when they arrived to the White House South Lawn on Monday evening.