Turkish President Recep Tayyip Erdogan has been accused of blatant sexism after declaring that women are not equal to men and claiming feminists in Turkey reject the idea of motherhood.

The devoutly Muslim president said that biological differences meant women and men cannot serve the same functions, adding that manual work was unsuitable for the "delicate nature" of women.

His comments ignited a firestorm of controversy on Twitter and one well-known female TV news anchor even took the unusual step of condemning the remarks during a bulletin.

"Our religion (Islam) has defined a position for women (in society): motherhood," Erdogan said at a summit in Istanbul on justice for women, speaking to an audience including his own daughter Sumeyye.

"Some people can understand this, while others can't. You cannot explain this to feminists because they don't accept the concept of motherhood."

He recalled: "I would kiss my mother's feet because they smelled of paradise. She would glance coyly and cry sometimes.

"Motherhood is something else," he said, claiming that it should be a women's priority because Islam exalts women as "mothers".

He went on to say that women and men cannot be treated equally "because it goes against the laws of nature."

"Their characters, habits and physiques are different ... You cannot place a mother breastfeeding her baby on an equal footing with men.

"You cannot make women work in the same jobs as men do, as in Communist regimes. You cannot give them a shovel and tell them to do their work. This is against their delicate nature."

Erdogan was apparently referring to the practise during and after World War II for women in Communist states like the USSR to do heavy manual work in factories or in roles such as tram drivers.

"What women need is to be able to be equivalent, rather than equal. Because equality turns the victim into an oppressor and vice versa."

Erdogan, 60, has been married since 1978 to his wife Emine, with whom he has had two sons and two daughters.