AYLESBURY, United Kingdom (AFP) — US President Donald Trump on Friday played down his extraordinary attack on Britain’s plans for Brexit, praising Prime Minister Theresa May and insisting bilateral relations “have never been stronger”, even as tens of thousands protested in London against his visit.

Trump’s first official trip to Britain was overshadowed by his warning that May’s plans for close ties with the EU would “kill” a future US trade deal, echoing concerns among eurosceptics in her Conservative party.

After talks at May’s country retreat of Chequers, miles away from the colourful crowds gathered to denounce his own domestic policies, Trump suggested he may have been hasty.

“Whatever you do is okay with us, just make sure we can trade together, that’s all that matters,” he told May at a press conference in the grounds of the 16th-century manor house.

“The United States looks forward to finalising a great bilateral trade deal,” he said, and repeatedly praised May’s leadership, saying she was a “terrific woman”.

Just hours earlier, The Sun tabloid published a bombshell interview with the president in which he suggested the prime minister’s Brexit proposal was not what voters wanted.

He said he had advised her to take another path, adding that Boris Johnson, who quit as foreign minister this week in protest at the plan, would make “a great prime minister”.

Trump denied Friday that he had criticised May, suggesting there was an element of “fake news” in the report – even though The Sun released audio recordings of his remarks.

His interview drew outrage among British politicians, who accused him of being “determined to insult” May after 18 months of testy relations between the pair.

They also fired up demonstrators in London.

Chanting “No Trump, no KKK, no fascist USA!”, they flew a huge balloon of the president depicted as a crying baby outside the Houses of Parliament.Even Londoners who did not join the protest, only stopping to take in the mass of people, placards and sloganeering, seemed supportive of the demonstrations.

“He brings it on himself — it’s like having a juvenile in charge of a superpower,” said construction worker Dan Kelly, 47.

– ‘Kill’ trade plans –

Britain voted to leave the EU in a referendum in June 2016, but after years of fighting within the government, only on Thursday published a detailed plan for what it wants.

The offer to follow EU rules in trade in goods sparked outrage among eurosceptics who want a clean break, and Trump appeared to back them.

“The deal she is striking is a much different deal than the one the people voted on,” he said in the interview conducted Wednesday.

His negative comments about a UK-US trade deal – viewed as one of the main benefits of leaving the EU by Brexit supporters – saw the pound fall although it later recovered its losses.

They also fuelled talk of rebellion in May’s Conservative party following the resignations of Johnson and Brexit secretary David Davis over the plan.

But Trump said Friday that after speaking with May’s officials and trade experts that a UK-US trade deal “will be possible”, adding that Brexit presented an “incredible opportunity”.

He admitted that Brexit was a “tough situation”, but warned: “You can’t walk away.”

May confirmed they had agreed to seek an “ambitious” free trade agreement, adding: “I’m clear our plan delivers on what the British people voted for.”

Even without opposition from Trump and at home, however, the prime minister still faces a major challenge to get the plan agreed with the EU.

Talks are due to resume in Brussels next week.

– ‘Tough on Russia –

The two leaders also emphasised their continued cooperation on defence and security, after earlier watching a display of special forces from both countries at the military academy at Sandhurst.

Trump thanked May for her support at a testy NATO summit this week in Brussels, where he subjected America’s other allies to a roasting over their defence spending.

Trump will spend the weekend at one of his Scottish golf courses before going to a summit in Finland on Monday between Trump and President Vladimir Putin.

May said they had agreed to engage with Russia with “strength and unity”, and Trump said he has been “tougher on Russia than anybody”.