President Donald Trump on Tuesday promised to “stay out” of Britain's election campaign during a two-day visit, while also seeking to defuse a key attack line against British Prime Minister Boris Johnson over healthcare.
Downing Street is braced for fireworks as Trump attends a meeting of the NATO military alliance in Britain, just days before a crucial election on Dec 12.
In his first press conference on Tuesday, the notoriously unpredictable US leader tried to avoid controversy in repeated questions about British politics.
I'll stay out of the election, Trump said, adding: I don't want to complicate it.
He declined to repeat his previous criticism of main opposition Labour leader Jeremy Corbyn, although he praised Johnson as very capable and I think he will do a good job.
But answering questions during talks with NATO chief Jens Stoltenberg, he could not stay out of an election issue that Labour has put at the heart of its campaign.
Corbyn claims US firms are seeking to exploit Britain's state-run National Health Service (NHS) in any UK-US trade deal London signs after leaving the European Union.
Trump fuelled the row on his state visit to Britain earlier this year by stating that everything would be on the table in any post-Brexit trade talks.
But Johnson said last week that if Washington tried to include the NHS in trade talks, we'd walk away.
On Tuesday Trump insisted: We have absolutely nothing to do with it and we wouldn't want to if you handed it to us on a silver platter.
The president confirmed he would be meeting Johnson, who is co-hosting the NATO summit, but it is not clear if the pair will have formal one-to-one talks.
There is speculation that, in the middle of an election campaign, Johnson wants to avoid appearing too close to a US president who is deeply unpopular in Britain.
Several hundred protests marched from Trafalgar Square towards Buckingham Palace, where Queen Elizabeth II held a reception for Trump and other NATO leaders.
Opinion polls suggest Johnson's Conservative party is heading for a comfortable win in next week's election, which has been dominated by Britain's looming EU exit.