The Republican Party’s shift to the Right, reflected by the rise of the Tea Party movement during the mid-term elections in 2010, has left it out of step with the Conservative Party on issues such as taxation, health care and rights for same-sex couples. Mr Cameron’s party is more in line with the Democrats in several areas.
Some British Tories continue to cultivate links. Greg Hands, the MP for Chelsea and Fulham, hosted Rick Scott, the Republican Governor of Florida, at the Houses of Parliament earlier this month. Mr Hands, who was born in New York, is himself a registered Republican in the US.
However, relations between transatlantic conservatives are a far cry from their 1980s heyday, when Ronald Reagan and Margaret Thatcher presented a united front - despite Mr Romney adapting Lady Thatcher’s famous “Labour isn’t working” election poster this year to claim: “Obama isn't working”.
Boris Johnson, the Conservative London mayor, has spoken of his admiration for Bill Clinton, the previous Democratic president, saying the “world was better run under him” and describing aspects of George W Bush’s leadership style as “terrible”.
Nile Gardiner, another foreign policy adviser to Mr Romney, previously described the Prime Minister’s behaviour in Washington as a “sad exercise in hero-worship before an extremely liberal White House”, which had shown itself willing to “knife London in the back” over the Falkland Islands.
“David Cameron’s wholehearted support for Barack Obama has significantly harmed the image of the British Conservative Party among US conservatives, who revere its greatest figures: Margaret Thatcher and Winston Churchill,” Mr Gardiner wrote after the visit.
None the less, spokesmen for Mr Romney have denied that there is disgruntlement in his camp regarding Mr Cameron's visit since this was first reported by The Guardian in May.
Under Mr Obama the US has remained neutral in the dispute between Britain and Argentina over the sovereignty of the Falklands, to the frustration of British diplomats. One member of Mr Romney's foreign policy advisory team said that it had been discussing the issue in some detail.
“There’s a great deal of sympathy and support for the British position,” said the adviser, who added: “Even though Argentina is more or less a friend, Britain is our oldest friend in the world.”
While the Republican candidate now emphasises his admiration of Britain, he has previously held it up as a post-imperial warning to those who would allow the US to decline. "England is just a small island," he wrote in his memoir 'No Apology'. "Its roads and houses are small. With few exceptions, it doesn't make things that people want to buy”.
The former Massachusetts governor will on Thursday also meet senior ministers Nick Clegg, George Osborne and William Hague, as well as Ed Miliband and Tony Blair. On Friday he will meet US athletes before attending the opening ceremony of the Olympics. Mr Romney was the chief executive of the 2002 Winter games in Utah.
His foreign policy advisers requested anonymity because they had been asked by Mr Romney's campaign not to criticise the President in foreign media.
A Downing Street spokesman stressed that Mr Cameron had met Mr Romney in London last year and maintained links with Republicans despite not having met any during March’s visit to Washington.
“It was a packed schedule, and was as close to a state visit as a head of government can do,” said the spokesman. “He wanted to focus on the relationship between the prime minister and the president.”
