British Prime Minister Boris Johnson met with US President Donald Trump late on Tuesday, and in response to a question about avoiding filming with Trump, Johnson said he would take pictures with all NATO leaders later.

Johnson, who is preparing for a general election on December 12, had asked Trump earlier not to interfere in the campaign. British newspapers say he is trying to avoid appearing with Trump, who is unpopular in Britain.

"We had a very good meeting and we discussed the future of NATO, what is happening in Syria and other security issues," Johnson told reporters.

"I enjoyed my meeting with British Prime Minister Boris Johnson at 10 Downing Street last night," Trump wrote on Twitter after the meeting. "We talked about a variety of issues including NATO and trade."

Johnson, whose country is hosting a summit of NATO heads of state, met with leaders of Germany, France and Turkey on Tuesday to discuss the Syrian crisis, and noted the importance of the US-led alliance remaining firm.

Trump announced yesterday that he would seek to stay away from the British election campaign, but will nevertheless meet Prime Minister Boris Johnson.

Asked by reporters during a meeting with NATO Secretary-General Jens Stoltenberg, he said: "I will stay out of the elections. I don't want to complicate it."

Opinion polls suggest the Conservatives are heading for a comfortable victory during the election, but Johnson's team is concerned about any provocative remarks from Trump, who cannot be predicted.

The Labor Party has sought to capitalize on Trump's visit to Britain by reiterating claims that Johnson would sacrifice free national health service in the UK as part of a trade deal with the United States after the Brexit, which both Johnson and Trump have denied.