WASHINGTON -- Mitt Romney's trip abroad was meant to illustrate his command of the international stage as he aims to deny U.S. President Barack Obama a second term in November.

Instead, there was this headline Thursday adorning one of the biggest and most respected newspapers in Great Britain, the Guardian: "Mitt Romney's Olympics blunder stuns No. 10 and hands gift to Obama."

The Guardian even featured a live blog devoted to Romney ridicule.

"Romney in London," read one Tweet highlighted on the blog. "Come on. We needed this. It's a little comic relief. Kind of like Mr. Bean, only he's an American."

Indeed, Romney's visit to the country considered America's closest ally has been a veritable public relations disaster, one that immediately got off to a bad start when an unnamed adviser told the Daily Telegraph that the candidate's "Anglo-Saxon heritage" means he can forge closer ties with Britain than Obama.

As Romney tried to distance himself from those remarks, the Republican presidential hopeful set off another firestorm when he suggested London wasn't properly prepared for the Summer Games.

"You know, it's hard to know just how well it will turn out," he told NBC News on Wednesday.

"There are a few things that were disconcerting, the stories about the private security firm not having enough people, supposed strike of the immigration and customs officials; that obviously is not something which is encouraging."

He even raised concerns about the Olympic spirit of the British, asking: "Do they come together and celebrate the Olympic moment? That's something which we only find out once the Games actually begin."

Prime Minister David Cameron was not amused.

"You're going to see beyond doubt that Britain can deliver," a testy Cameron told reporters on Thursday.

"We are holding an Olympic Games in one of the busiest, most active, bustling cities anywhere in the world. Of course it's easier if you hold an Olympic Games in the middle of nowhere," he said in apparent reference to the Salt Lake City Olympics managed by Romney in 2002.

London Mayor Boris Johnson joined in on the pile-on on the eve of the Games' opening ceremonies later Thursday.

"There's a guy called Mitt Romney who wants to know whether we're ready. Are we ready? Are we ready? Yes we are!" Johnson told a cheering crowd of about 60,000 people in Hyde Park.

During a 45-minute meeting at 10 Downing Street earlier Thursday, Cameron reportedly raised his dismay about the remarks. Romney emerged from the meeting with a decidedly different tone.

"I am very delighted with the prospects of a highly successful Olympic Games," he said. "What I have seen shows imagination and forethought and a lot of organization and I expect the Games to be highly successful."

The White House, meantime, made a point of highlighting the president's "full confidence" in Britain's ability to host a secure Olympics.

"In keeping with our special relationship, the president also made it clear that he has the utmost confidence in our close friend and ally, the United Kingdom, as they finalize preparations to host the London Olympics," said White House press secretary Jay Carney.

And yet Romney's gaffes didn't stop at the Olympics. He also mentioned meeting with the head of the top-secret MI6 British intelligence agency, something considered a protocol lapse.

Even the right-wing British media were critical.

"Who invited him?" asked the The Daily Mail, going on to call Romney's British visit "humiliating."

The paper's political editor, James Chapman, provided a Twitter play-by-play of Romney's very bad day. The most damning came from Chapman's Whitehall sources, whom he said branded the candidate "worse than Sarah Palin."

There was still more. Romney was also described as "devoid of charm, warmth, humour or sincerity,"' Chapman tweeted.

The Daily Mail also reported on what it considered another gaffe, calling it "cringe-worthy" when Romney referred to British opposition leader Ed Miliband as "Mr. Leader" after the two men sat down for their own meeting. Other media suggested Romney had forgotten Miliband's name.

Times of London columnist Janice Turner wondered how Romney will manage trips to actual troublespots.

"So Mitt Romney disses our Olympics. We're the Special Relationship, the easypeasy bit of US foreign relations. How will he deal with China?" she Tweeted.

Romney has also raised eyebrows for a fundraiser Thursday night that was expected to attract employees of Barclays bank, the first financial institution to confess to manipulating a key market index.

Bob Diamond, the disgraced former head of Barclays, was slated to host the fundraiser but has since cancelled. Barclays has been fined US$453 million by American and British authorities.

After attending the opening ceremonies of the London Games on Friday, Romney might be relieved to see the last of Great Britain when he heads to Israel on Saturday. He'll then visit Poland on Monday, meeting in both countries with public and private officials.