Ukip's treasurer believes women are less suited than men to engineering jobs - but thinks they're better at "caring professions".
Stuart Wheeler explained the differences between the genders' strengths as he was asked to clarify controversial comments about women on boards.
In a panel debate, the former Tory donor and businessman had claimed women's unsuitability for some professions was illustrated by their poor performance at chess and bridge.
This sparked an angry reaction from a fellow panellist, Clare Gerada, who chairs the Royal College of GPs.
On Thursday, Wheeler was challenged on his comments on the BBC's World at One show.
Setting the scene, he said his fellow debaters had all agreed on the need for quotas to even things up in the boardroom.
"I thought it was about time to interject with a little bit the other way," he said.
"I pointed out that in certain areas, women don't do as well as men."
Aside from physical sports, these included poker, bridge and chess, he said.
"This lady, Gerald [Clare Gerada] leapt to her feet, and said 'look at my 83-year-old mother, she's terribly good at bridge'..that seemed to be a reason to say my remark was sexist".
He said he was not saying men were more intelligent, because often women do better at university.
"It's very difficult to pin your hand on exactly what it is," he said.
Wheeler said there were few women working in engineering, but many more in "caring professions", adding: "Women and men make different choices."
"All I was saying is that there are areas where women are not as good as men and I am sure there are area where men are not as good as women."
Wheeler said it was not "crucial" to have a minimum number of women on an engineering board, in the same way as there didn't need to be a minimum number of men on a hospital board.
"My point is that there are some things that men are better than women at, and some things that women are better at than men, and I don't want to impose minimum numbers of either on any board."
Ukip are "very keen" to recruit more women, he said, but not through quotas.