David Cameron has told a would-be Tory councillor in Manchester she is in "the wrong party" after she opposed the idea of an ethnic minority candidate.
Mr Cameron has said the Tory candidate is in the wrong party
Joan Howarth said in an interview Denton and Reddish was a traditional working class seat and an ethnic minority candidate "wouldn't work".
The Tory leader responded by saying Mrs Howarth was unrepresentative of the "modern Conservative Party".
She later apologised and said it was not what she really believed.
In a statement Mrs Howarth, who plans to stand in the 4 May council elections, said: "I completely and utterly regret what I said to Channel 4.
"It was not what I meant or believe at all. I totally support David Cameron's moves to make the Conservative Party more inclusive and to have more candidates from black and ethnic minority communities.
"I believe that candidates should be able to stand everywhere regardless of the ethnic make-up of the constituency in question."
It is vital the party makes progress on this issue, she added.
The spat follows a row after Mr Cameron accused UKIP of being "closet racists".
The UK Independence Party later retracted threats to sue the Tory leader but they are demanding an apology.
Mr Cameron said of Mrs Howarth's remarks: "She is in the wrong party She is unrepresentative of the modern Conservative party. At the last election we had more candidates from the black and ethnic minority communities than any other party."
UKIP Euro MP Nigel Farage said: "This is Cameron's boomerang. He tried to throw a stick at us and it has come back to hit him very hard.
"The UK Independence Party is a damn sight more cosmopolitan than the Conservative Party."
Labour's Phil Woolas also waded into the row calling on Mr Cameron to "take decisive action" over the issue.
"He says one of his candidates is in the wrong party but three days after her revealing outburst on ethnic minorities on national television, he has failed the test of leadership by refusing to take action," said the local government minister.