May said the most important thing was that Trump would be going into the meeting with Putin with the 29-strong North Atlantic Treaty Organisation military alliance united behind him.
Negotiations would then be widened to include members of both delegations, he said, adding that Russian Foreign Minister Sergei Lavrov will hold parallel talks in Helsinki with his USA counterpart, Mike Pompeo.
Lawmakers on both sides of the aisle on Friday called on President Donald Trump to consider canceling his summit with Russian President Vladimir Putin set for next week in Finland following a new indictment in the Russia investigation.
"This was not an attack on Republicans or an attack on Democrats - this was an attack on the United States", he added. All patriotic Americans should understand that Putin is not America's friend, and he is not the President's buddy.
Trump claimed he would be going into the meeting with Putin with North Atlantic Treaty Organisation better financed, more united and resolute. He said the one-on-one meeting should not take place until "Russia takes demonstrable and transparent steps to prove that they won't interfere in future elections". Imagine if Theresa May came to the White House, into the Rose Garden, and said publicly, with the president standing behind, beside her, I think that Jeff Flake or Bob Corker or John Kasich would make a very good president of the United States.
Israel says it hits Syrian army posts after drone incursion
The Netanyahu government is detemined to keep fighters loyal to Assad and to Iran out of the Syrian Golan border area near Israel. Russia, another top key ally of Assad, has warned it would be unrealistic to expect Iran to fully withdraw from the country.
Weighing in on the matter during Jake Tapper's CNN show, the panel expressed their concerns about the planned meeting, including Trump's ability to be a worthy negotiator against the current Russian president and former KGB agent.
Earlier Friday during a press conference overseas with his British counterpart, Trump vowed to press Putin about his government's interference in the 2016 American election - though he appeared to leave open, as always, the possibility that he won't.
"I don't think you'll have any 'Gee, I did it, I did it, you got me, '" Trump said Friday morning before the indictments were announced. "And, today, Special Counsel Mueller indicted twelve Russian military officers for hacking the Democratic National Committee - a direct attack on our democracy".
But the indictment identifies the defendants as officers with Russia's Main Intelligence Directorate of the General Staff, also known as GRU.