Mitt Romney and David Cameron
Republican presidential hopeful Mitt Romney shaking hands with British Prime Minister David Cameron in London Thursday. USA Today

Before Mitt Romney flew to London for a trip that is part-fundraiser and part-audition as the leader of the free world, he told NBC's Brian Williams that Britain's preparations for the Olympic Games have been "disconcerting." That and a few other gaffes haunted the former Massachusetts governor all day Thursday, as Romney was hounded by the British press and openly mocked by Boris Johnson, London's mayor, in front of 60,000 people.

"The stories about the private security firm not having enough people, the supposed strike of the immigration and customs officials - that obviously is not something which is encouraging," the Republican candidate told Williams in an interview that aired Wednesday.

"Do [British people] come together and celebrate the Olympic moment? And that's something which we only find out once the games actually begin," Romney said. "It is hard to know just how well it will turn out."

On Thursday morning, London's newspapers greeted Romney with the story as their main headlines, according to Politico. The conservative Daily Telegraph's front page read, "Mitt Romney Questions Whether Britain Is Ready For The Games."

Even British Prime Minister David Cameron addressed Romney's comments, reports The Guardian.

"We'll show the world we've not only come together as a United Kingdom but are extremely good at welcoming people from across the world," Cameron said. "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. Inevitably, you're going to have challenges."

"Middle of nowhere" could be perceived as a reference to Salt Lake City, where Romney led the Winter Games in 2002.

Romney met with the press during the day Thursday and before he even took any questions he seemed to acknowledge his comments by starting off with, "I applaud the work the organizers did in bringing the Olympic experience right into the heart of London."

Later in the day, Johnson didn't hesitate to tear into Romney at a celebration that marked the end of the Olympic torch relay.

"There are some people who are coming from around the world who don't yet know about all the preparations we've done to get London ready in the last seven years," Johnson said. "I heard there's a guy called Mitt Romney who wants to know whether we're ready. Are we ready? Yes we are!"

Perhaps most damning was the crowd responding to Johnson's pump-up speech by chanting "Yes We Can!" the seminal slogan from President Barack Obama's 2008 presidential campaign.

The other flub that's made headlines both domestically and abroad is Romney's admission that he met with the head of MI6, the British equivalent of the CIA. The difference between the two spy agencies is that MI6 is much more under wraps, it's existence was only acknowledged in 1994.

"I appreciate the insights and perspectives of the leaders of the government here and opposition here as well as the head of MI6," Romney said to reporters. "We discussed Syria and the hope for a more peaceful future for that country."

According to the Wall Street Journal, an aide in Britain's foreign press office wouldn't confirm or deny the meeting with MI6 chief Sir John Sawers took place. "Sir John Sawers meets with lots of people, but we don't give a running commentary of any of these meetings."

On a much smaller level, the presumptive GOP nominee also broke the normal rule that U.S. politicians don't criticize the president while they're overseas. At a fundraiser Romney reportedly said, "I'm looking forward to the bust of Winston Churchill being in the Oval Office again." The Huffington Post reported that Obama replaced the bust with a rendition of Abraham Lincoln after he was inaugurated.

As if the perception couldn't get any worse for Romney, he ended Thursday in London with a fundraiser. Only it was one that was supposed to be hosted by Bob Diamond, former head of Barclays, who had to back out after losing his job because of the Libor scandal.