In an antagonistic interview with The Sun, the USA president lashed out at Sadiq Khan, accusing him of doing a "terrible" job, claimed Boris Johnson would make a great Prime Minister and made it clear he was very aware of the giant inflatable Trump baby due to fly above Parliament today - and would be avoiding London.
Trump said May "didn't listen" to his views on how she should negotiate Brexit, but that was "fine".
"I said very good things about her" in the interview, Trump said.
Mr Trump said he thought Mr Johnson would make a "great Prime Minister" and that he was "saddened" the former foreign secretary was out of the government.
Opponents of Donald Trump flew a six-meter blimp depicting the USA president as an orange, snarling nappy-wearing baby just outside the British parliament on Friday.
The president told Mrs May she had to maintain "momentum" because "if it drags out the deal doesn't get done", according to Mr Bannon.
"If they do a deal like that, we would be dealing with the European Union instead of dealing with the United Kingdom, so it will probably kill the deal".
I have no power over these things."The latest chapter in the Trump-Khan feud came after a British lawmaker was accused of Islamophobia over a now-deleted tweet he posted about the London mayor.Michael Fabricant posted a cartoon Khan's head on an inflatable balloon, engaged in a sex act with a pig". I haven't been there in a long time. I think she is a nice person. "I think he has done a very bad job on terrorism".
British Prime Minister Theresa May and U.S. President Donald Trump stand together upon Trump's arrival for a meeting at Chequers, the PM's country residence, on July 13, 2018.
Ahead of the U.S. leader's visit, Khan gave permission for a 20-foot-tall "Trump Baby" blimp to be flown above Parliament Square which Trump said made him feel "unwelcome" in London.
Although Trump has said this practice will be stopped, thousands of children remain separated from their parents and face great difficulty locating their relatives.
London Mayor Sadiq Khan defended his decision to give permission for the blimp to be flown, saying it was not for him to be a censor or to decide what is in good or bad taste.
The Trumps landed in Air Force One at Stansted Airport at lunchtime on Thursday to kick-start a four-day working visit to Britain as protests against his trip began.
The British government on Thursday published its long-awaited Brexit blueprint aimed at restarting stalled talks with the European Union, only for it to be panned by eurosceptics, the City of London and the United States president. He said: "The people voted to break it up, so I imagine that's what they'll do".
"I don't think it will kill the deal".
She is our Prime Minister.
Trump has insisted the US-UK relationship is "the highest level of special".