A Lib Dem councillor in Manchester has defected to the Conservatives, giving the party its first seat on the city's council for more than a decade.
Faraz Bhatti stood for Lib Dems at the 2005 General Election
Faraz Bhatti, 34, who also stood at the 2005 election, said the Lib Dems were "too protective of their own positions in the town hall".
Mr Cameron told the same paper it showed the Conservatives were "the true home of progressive politics".
He met Mr Bhatti earlier, while in the city for a major speech on the NHS.
Mr Cameron said he was "delighted" at the news adding: "For the first time in 11 years, we now have a Conservative on Manchester City Council.
"I look forward to working with Faraz and our Conservative activists in Manchester to tackle crime and improve the quality of life for people in Manchester."
He said the Conservatives were "the true home of progressive politics".
Meanwhile Mr Bhatti said the Tory leader had brought the party "back to the centre ground of British politics".
He added: "Manchester needs a real opposition to question the decisions of the Labour Council. The Liberal Democrats have, I'm afraid, become inward looking and too protective of their own positions in the town hall."