Anne Hidalgo, the Socialist city council leader, threatened to sue for discrimination leaders of the Mwasi "Afro-feminist" association, which is planning to hold the inaugural Nyansapo Fest over two days in July.

She promised to seek to ban the event after the association said 80 per cent of discussions, which aim to build “Afro-feminist strategies to end racial, patriarchal, colonial and capitalist violence”, would be reserved for black women only.

A second debate on “Afro-struggles” would be open to black people of both sexes, it said, while a third, on “decolonial feminism”, would be open to women of all ethnic origins who had suffered from racism. Only one exhibition is open to all.

Ms Hidalgo said on Twitter that she firmly condemned the organisation “of this event, ‘prohibited to white people’”.

“I am asking for this festival to be banned,” the mayor said, adding she also reserved the right “to prosecute the organisers for discrimination”.

The venue is an embarrassment for the mayor as it is due to take place in premises owned by the Paris council.

Anti-racism groups strongly condemned the festival, with SOS Racisme calling the event “a mistake, even an abomination, because it wallows in ethnic separation, whereas anti-racism is a movement which seeks to go beyond race”.