Trump said it was "sort of a double negative," adding, "I think that probably clarifies things pretty good by itself."
That didn't go down too well online:
It was also pointed out he made a handwritten note of his own during his "clarification" moment.
Despite saying he now accepts the intelligence community's verdict on Russia, he's written a misspelled note that says "THERE WAS NO COLUSION".
CNN's chief political analyst Gloria Borger said: "This president looked like he was in a hostage situation, reading from a script that others had written for him, that he clearly did not want to read."
At the Helsinki summit, Trump appeared to unquestioningly accept the Russian President's "strong and powerful" denials of meddling in the election.
Putin asserted his country had "never interfered, and does not plan to interfere in internal American electoral process".
Trump said: "All I can do is ask the question. My people came to me, (director of national intelligence) Dan Coats came to me and some others. They said they think it's Russia.
"I have President Putin. He just said it's not Russia. I will say this. I don't see any reason why it would be."
But he faced a significant backlash, with former president Barack Obama condemning the "politics of fear, resentment, retrenchment" in a stinging rebuke.
"Each day's news cycle is bringing more head-spinning and disturbing headlines," Obama said, calling these "strange and uncertain times we are in".
Obama urged people around the world to respect human rights and other threatened values in his most high-profile speech since leaving office, at the 100th anniversary of Nelson Mandela's birth in South Africa.
"We see much of the world threatening to return to a more dangerous, more brutal, way of doing business," he said.
He did not directly mention Trump, but his comments were clearly a response to the President's heavily criticised performance in Helsinki.
"I am not being alarmist, I am simply stating the facts," Obama said. "Look around."
He also spoke for equality, saying that "I would have thought we had figured that out by now."
— with US correspondent Emma Reynolds