The United Nations has come under fire for appointing the comic book superhero Wonder Woman as its new Honorary Ambassador for the Empowerment of Women and Girls.

The appointment was made on Friday- the character’s 75th birthday - to mark the launch of a year-long social media campaign to promote female empowerment.

But the appointment was met with outrage from UN members and feminists worldwide, who have now lunched an online petition (already with over 2,400 signatures) to remove the character from her post, on the grounds that she is not an appropriate candidate.

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Wonder Woman’s appointment was made despite an international campaign to elect a woman as UN secretary-general. But of the five female candidates in a list of 10, a woman did not get the role. And recent analysis found that nine out of 10 senior leadership roles at the UN went to men.

Protesters have dubbed the appointment 'reductive', noting their disappointment that the UN opted for a fictitious character, instead of a real human woman, to champion the rights of women. The online petition says: “It is alarming that the United Nations would consider using a character with an overtly sexualized image at a time when the headline news in United States and the world is the objectification of women and girls.”

Around 100 UN staff members protested the appointment holding placards in the lobby of the UN that read: “I am not a mascot,” Let’s get real” and “real women deserve a real ambassador”.

Speaking to the BBC, one UN staff member said: “We don’t think that a fictitious comic book character wearing what basically looks like a playboy bunny outfit is really the right message we need to send to girls – or even boys for that matter – about what strong women are. We think that is a toxic message to be sending.”

Gloria Steinem told CBS that she was “all for symbolism,” but that “we are now looking for women with real terrestrial power”.

Professor of global affairs at New York University, Anne Marie Goetz, called the decision “disgusting,” and social media erupted with suggestions of real-life women who would better fit the role.

But some have said the comic book character was appointed due to her feminist status.

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UN official Maher Nasser said that “The focus [of the UN] was on her feminist background, being the first female superhero in a world of male superheroes and that basically she always fought for fairness, justice and peace.”

It’s not the first time a fictional character has been appointed as a UN ambassador. In 1998, Winnie the Pooh was appointed as ambassador for Friendship, and in 2009, Tinker Bell was honorary ambassador of green.

The news comes not long after Wonder Woman came out as queer, and a new Wonder Woman film is set for release.