Peter MacKay, deputy leader of the Conservative party, has apologized to New Democrat Alexa McDonough for telling her to "stick to her knitting."

The two longtime Nova Scotia MPs running for re-election appeared on a Halifax radio show on News 95.7 Friday.

McDonough and MacKay were sparring about constituency races in Nova Scotia. When he said she was using her reputation to drag NDP candidates across the finish line, she defended the NDP candidate running in his riding.

"We'll just see what happens," MacKay replied. "I think you better stick to your knitting and win your own riding."

McDonough immediately asked him if that was a sexist reference, and he said it wasn't. Then she said she would be delighted to have time to knit after the election because she has five grandchildren.

But after the radio program, McDonough told reporters she was surprised by his "sexist slur."

MacKay says he has called McDonough personally to apologize.

"My understanding was it meant 'mind your own business or stay with the things you know.' It certainly was never intended to offend anyone, particularly women," MacKay said.

He also sent a written apology to the offices of the Nova Scotia Advisory Council on the Status of Women and the local women's centre in his riding of Central Nova.

It's not the first time MacKay and McDonough have needled each other during an election campaign.

In 2004, McDonough challenged MacKay to a debate. He agreed but only if she travelled to his riding. He said the challenge was typical of McDonough because "she likes her stunts and gimmicks and she likes to rant."

McDonough laughed off the reaction to that challenge.