The United Nations celebrated Wonder Woman's 75th birthday on Friday by naming the comic book character as its new Honorary Ambassador for the Empowerment of Woman and Girls, despite frustration from both inside and outside the world organization that the spot should go to a real — and less sexualized — woman.

The ceremony at the Economic and Social Council chamber, was marred by some 50 U.N. staffers who silently turned their back to the stage, some with their fists in the air.

United Nations staff stand and turn their backs, top, in a silent protest to the decision to designate Wonder Woman an honorary ambassador. (Bebeto Matthews/Associated Press)

The super heroine's image will be used by the U.N. on social media platforms to promote women's empowerment, including on gender-based violence and the fuller participation of women in public life (using #WithWonderWoman). The push, hoping to reach young people, is backed by DC Entertainment and Warner Bros., which produce both comics and films featuring Wonder Woman.

But an online petition started by U.N. staffers asked the Secretary General to reconsider the appointment. As of Friday afternoon, it had more than 1,100 signatures.

"The message the United Nations is sending to the world with this appointment is extremely disappointing. The bottom line appears to be that the United Nations was unable to find a real life woman that would be able to champion the rights of all women on the issue of gender equality and the fight for their empowerment," organizers wrote.

Honorary ambassadors — as opposed to goodwill ambassadors like Nicole Kidman and Anne Hathaway — are fictional characters. The U.N. previously tapped Winnie the Pooh to be an honorary Ambassador of Friendship in 1998 and Tinker Bell as the honorary Ambassador of Green in 2009. But the protest on Friday seemed to unnerve many of the U.N.'s press officers.

'It's OK that not everyone agrees'

Friday's event brought together actress Lynda Carter, who played Wonder Woman in the 1970s TV series, and Gal Gadot, who has taken on the role in the forthcoming Wonder Woman film, as well as Girl Scouts in Wonder Woman T-shirts and U.N. staffers' kids who skipped school.

Patty Jenkins, left, director of the upcoming Wonder Woman movie, and star Gal Gadot, listen during a UN meeting designating Wonder Woman an honorary UN ambassador. (Bebeto Matthews/Associated Press)

Diane Nelson, president of DC Entertainment, gave a speech in which she argued that stories — even comic book stories — can "inspire, teach and reveal injustices."

Carter, who gave a moving speech about how Wonder Woman embodies the inner strength of every woman, was the only one to acknowledge the protesters in her remarks, saying "Please embrace her. To all those who don't think it's a good idea, stand up and be counted."

United Nations staff held a silent protest against the decision to designate Wonder Woman as an honorary UN ambassador. (Bebeto Matthews/Associated Press)

Afterward, she said: "It's OK that not everyone agrees, but get over it and say, 'What else is new?'"

The actress noted that she has weathered criticism of the role for years.

"In the beginning, in the '70s, it was 'Well, she's objectified.' It's like, 'She's too tall, she's too this, she's too this,"' Carter said. 'Oh, she wants to be a feminist?"'

As for Gadot, she said after the event that, "I'm the kind of person who always looks at the half-full glass. I care for the people who care and I'm here for a wonderful cause today."

She added, through a thin smile: "That's all what my focus is."

Real heroines preferred

But among those thinking the glass was half empty was Shazia Z. Rafi, who previously worked at the U.N. and is now managing director of the consulting firm Global Parliamentary Services. She argued that the choice of Wonder Woman was tone deaf at a time when real women are fighting against sexual exploitation and abuse.

"I think it's a lot of rubbish that you can appoint a cartoon female to represent gender equality in this day and age, even if it is to reach younger women," said Rafi. "I'm not against cartoons. I think cartoons have a value. But that is not the issue."

Rafi said there were plenty of real heroines that could be the face for gender equality, including Nadia Murad, who has become the public face of the thousands of Yazidi women and girls who remain in sexual slavery, and Malala Yousafzai, who defied the Taliban to demand that girls be allowed to receive an education.

This whole issue of taking a cartoon figure who is clad in a bustier, with cleavage, high-cut shorts — a sort of muscled version of a Barbie — and saying '"This is what represents gender equality" is incredible. It's culturally insensitive. It's insulting. - Shazia Z. Rafi

The Wonder Woman appointment came after many women were dismayed that another man, Antonio Guterres, the former prime minister of Portugal, was chosen to be the next secretary-general. Over 50 countries and many organizations lobbied for a woman and seven of the 13 candidates to replace Ban Ki-moon on Jan. 1 were women — but none placed above third in the six informal polls.

Rafi, who had campaigned for a woman to be appointed the world's diplomat-in-chief, called it a "slap in the face of all women who work within the U.N." She said the decision to name Wonder Woman as an ambassador was effort to appease disappointed staffers.

Rafi and the petition also takes issue with Wonder Woman's skimpy outfit, arguing that the world might not embrace a scantily clad character in a shimmery, thigh-baring body suit with an American flag motif and knee high boots.

Though Wonder Woman has undergone many changes over the years, in the comics and onscreen, the classic image of her endures. (DC Comics)

"This whole issue of taking a cartoon figure who is clad in a bustier, with cleavage, high-cut shorts — a sort of muscled version of a Barbie — and saying 'This is what represents gender equality' is incredible. It's culturally insensitive. It's insulting," said Rafi.

It is not the first time the United Nations has partnered with a huge media company. In March, the U.N. appointed Red, the leader of the Angry Birds mobile game characters, as an envoy to tackle climate change. That campaign is in partnership with Sony Pictures Entertainment.