In a tabloid interview, he criticized May's Brexit plans, said he might no longer be open to a trade deal with the United Kingdom, and said one of May's political rival would be an excellent prime minister, undermining her at a time when her government is in turmoil.
He did not directly mention Trump, but his comments were clearly a response to the President's heavily criticised performance in Helsinki.
"Just by standing on the stage honouring Nelson Mandela, Obama is delivering an eloquent rebuke to Trump", said John Stremlau, professor of worldwide relations at Witwatersrand University in Johannesburg. Rand Paul defended the president on "CBS This Morning," saying the president "did a good thing" by meeting with Putin.
Trump's defense of Russian President Vladimir Putin's hostility toward democracies around the world and his refusal to hold the Russian leader accountable provoked bipartisan outrage and confusion.
Trump took to Twitter early Wednesday to defend his Putin meeting, promising "big results" from better relations with Russian Federation and hitting back at "haters".
The blowback for Helsinki was so fierce that Trump issued a uniquely rare walk-back, saying he meant to use a double negative and indicate Russian Federation would be responsible for the election hacking.
Rick Wilson, a conservative who has always been critical of Mr Trump, says elected party members are horrified by his latest controversy.
When he said he couldn't see how it "would" have been Russian Federation that was responsible for election interference, he says he actually meant to say he couldn't see how it "wouldn't" have been Russian Federation. He is pushing legislation with Democratic Sen. "Russia is a bad actor, and we must treat them as such".
The event went so badly that Trump was forced out in front of cameras to run back his comments Tuesday, which he then negated by repeating the same statements made Monday.
Douglas Brinkley, a presidential historian and professor at Rice University, compared Trump to "a bull carrying his own china shop around with him".
'The sentence should have been "I don't see any reason why it wouldn't be Russia"'. And the scripted cleanup pertained only to the least defensible of his comments.
"Ultimately I can tell you what I know, the Russians most certainly under the direction of President Putin interfered in our election, primarily for the purposes of putting a cloud over the head of the next president, no matter who won", Rubio said.
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