“It is important & timely that they’ve apologised,” Ngozi Okonjo-Iweala said in a tweet.

The development economist took over as the new WTO chief today after a long, high-powered career serving as minister of finance and foreign affairs in her native Nigeria and 25 years at the World Bank.

But when several Swiss newspapers announced her appointment last month, they decided the most noteworthy thing to mention about the new WTO chief was as a matriarch.

“This grandmother will become the boss of the WTO,” read the headline of the article published by the Aargauer Zeitung and several other papers on Feb 9.

After a number of women heads of UN agencies and more than 120 ambassadors in Geneva last week signed a petition calling out the headline as racist and sexist, the paper apologised.

“This headline was inappropriate and unsuitable … We apologise for this editorial mistake,” the paper’s foreign editor-in-chief Samuel Schumacher said in a statement on Friday.

In her tweet, Ngozi welcomed the apology and said she was “thankful to all my sisters, UN Women Leaders and the 124 Ambassadors in Geneva who signed the petition on calling out the racist & sexist remarks in this newspaper”.

“We need to call out this behaviour when it happens,” she insisted, decrying the stereotypes women face when they take on leadership positions.

She said the headline debacle reflected the problems raised in a book she co-authored with former Australian prime minister Julie Gillard called “Women and Leadership”.