Republican presidential candidate Mitt Romney says it's not clear whether Britain can overcome the issues that have dogged its final preparations for the London Olympics.
In an interview broadcast Thursday with NBC News, Romney said "it's hard to know just how well it will turn out."
He cited problems with a security contractor that struggled to provide enough guards for sporting venues -- prompting Britain to call up extra troops -- and worries over a planned strike by immigration staff, a walkout that has since been averted.
Romney served as the head of the 2002 Winter Games in Salt Lake City.
British Prime Minister David Cameron, who was meeting with Romney later, told reporters that the U.S. candidate and others would soon "see beyond doubt that Britain can deliver."