Republican leaders clash over credibility

Republican presidential candidates Mitt Romney and Rick Perry accused each other in a debate of contradicting themselves on issues such as healthcare and social security retirement benefits.

Mr Perry, the Texas Governor, has overtaken Mr Romney, a former Massachusetts Governor, as the frontrunner. Seven other candidates also took part, but with five months to go before the first nominating contests the Republican battle is turning into a two-man race.

Thursday's debate, the third in as many weeks, focused on character and credibility. Mr Perry, pictured, insisted he had backed off "not one inch, Sir" from what he had written in a campaign-season book published a few months ago.

Mr Romney vouched for his own steadfastness moments later. "There are a lot of reasons not to elect me," he said. "There are a lot of reasons not to elect other people on this stage ... But one reason to elect me is I know what I stand for. I've written it down. Words have meaning."