He claimed the rules which prevent employers from asking job applicants if they plan to get married and have children result in some companies simply throwing away women's CVs.

But Theresa May, the Conservative Party's women's spokeswoman, accused him of having an "outdated" attitude.

She said: "It's about time that people like Alan Sugar stopped taking an outdated view of women in the workplace, stopped talking about why employing women is such a problem for business and started talking about why employing women is good for business. I would like to challenge Sir Alan to repeat his comments to some of our female (parliamentary) candidates."

Launching a report on the party's priorities for women yesterday, Ms May said that the persistence of a 17 per cent gender pay gap was wrapped up with the outmoded cultural attitudes reflected in Sir Alan's remarks.

She also accused the Labour government of failing women by neglecting to enforce laws introduced to protect them.

In an interview earlier this week, Sir Alan said that the possibility that a job applicant might take time off to have a child was "a bit of a psychological negative thought" in employers' minds and many would like to ask women about their plans.

"They would like to ask the question: 'are you planning to get married and to have any children?' " he said. "These laws are counter-productive for women, that's the bottom line. You're not allowed to ask, so it's easy – just don't employ them. It will get harder to get a job as a woman."

But Michelle Mone, the Scots entrepreneur behind the Ultimo lingerie line, last night insisted that women were often better employees after becoming mothers.

She added: "I really respect Alan Sugar and he has always impressed me. He has his opinion and I have mine and mine is that women make a valuable contribution to the workplace. In fact, I would argue that often women work better and harder after they have children."

Mary Senior, the assistant secretary at the STUC, said: "His comments underline why we need laws to protect women and other groups who may be marginalised by other unscrupulous employers who share this view.

"Women have lots to contribute to the workplace, so it's important that their skills are embraced."