A row has broken out between the campaigns of two leading contenders for the Democratic Party nomination in next year's US Presidential election.
The campaign teams of Senators Hillary Clinton and Barack Obama clashed following comments by the Hollywood mogul, David Geffen, who hosted a fundraising event this week for Senator Obama.
Mr Geffen, who once backed Bill Clinton, was quoted as describing Ms Clinton as 'overly ambitious and polarising' and her husband as 'reckless'.
The Clinton campaign has demanded that Mr Obama denounce the remarks but he refused.
While campaigning in Iowa, Mr Obama said it was not clear to him why he should apologise 'for someone else's remarks'.
He said that while Mr Geffen may have differences with the Clintons, that had nothing to do with his campaign.
Later, Ms Clinton dodged the issue at a Nevada candidates' forum moderated by her husband's former communications director George Stephanopoulos.
She said she wanted to run a 'very positive' campaign and did not want Democrats or Democratic supporters to be engaging in 'the politics of personal destruction'.
