Britain's ambassador in the US has been "engaging" with the frontrunner for the Republican presidential nomination, Donald Trump, Downing Street has confirmed.
The prospect of Mr Trump succeeding Barack Obama as president is an awkward one for David Cameron, after he blasted him last year as "divisive, stupid and wrong" for his comments on excluding Muslims from the US.
The decision to put out diplomatic feelers to the Trump team will be seen as an indication that Number 10 is attempting to build bridges in preparation for the possibility of having to deal with the property tycoon in the White House.
Asked whether diplomats had been told to establish contacts with Mr Trump, the Prime Minister's official spokeswoman said that this was "part and parcel of what we do".
The spokeswoman said: "It's a well-known job for our ambassadors and embassies to know the leading political figures wherever they are in the world and to engage with them.
"Obviously, as we get close to the point where nominees for the US presidency are decided, it makes sense to ensure we have got good links with those candidates.
"This is about the engagement that happens between Government and differing political teams around the world in the run-up to elections. It is the type of thing we would have done with elections in the past in terms of engaging with leading candidates."
Prime ministers are traditionally wary of making any public comment about candidates in elections overseas, for fear that they may be accused of attempting to interfere in the democratic decisions of foreign nations, or that their words may come back to bite them if they later have to deal with the candidate in office.
But Mr Cameron was trenchant in his criticism of Mr Trump last December, when Parliament debated a petition to ban him from the UK over his call for a "total and complete shutdown of Muslims entering the United States".
Speaking in the House of Commons, the PM opposed a travel ban on Mr Trump, but added: "I think his remarks are divisive, stupid and wrong. If he came to visit our country I think he would unite us all against him."
At the time, Mr Trump was widely regarded as a maverick candidate who would struggle to translate his popular appeal into a Republican nomination or a credible bid for the White House.
After a series of victories in state primaries, the reality TV star has now established a commanding lead in the race to secure the 1,237 delegates needed for nomination at July's Republican National Convention. However, polls suggest he faces a tough challenge closing the gap on his most likely Democrat rival for the presidency, Hillary Clinton.
Asked whether Mr Cameron was now distancing himself from his earlier comments, the PM's spokeswoman said: "You have got the Prime Minister's words and they are what they are."