The Cannes Film Festival is coming under scrutiny for its policy of only allowing women dressed in high heels to walk on the red carpet for its formal premieres.  

Cannes high heels-only flap2:28

Many are criticizing the festival after Screen International reported that several middle-aged women were turned away from the Sunday premiere of Carol for wearing flats.

At the media conference for Sicario on Tuesday, actress Emily Blunt called the report "very disappointing." 

"Everyone should wear flats, to be honest," said Blunt. "We shouldn't wear high heels anyway, that's my point of view. I just prefer wearing Converse sneakers."

Sicario director, Montreal's Denis Villeneuve joked that he would lead a demonstration against the dress code at his film's evening premier with film's male cast.

"In a sign of protest," Villeneuve told the press conference, "Benicio [Del Toro], Josh [Brolin] and I will walk the stairs in high heels tonight."

Controversy called 'Shoegate'

The red carpet at Cannes is highly regulated by tradition. Men are expected to wear tuxedos, women dresses and heels. The dress code isn't explicitly spelled out by the festival but is enforced by security guards.

FILMFESTIVAL-CANNES/

The dress code isn't explicitly spelled out by the festival but is enforced by security guards. (Regis Duvignau/Reuters)

Festival spokeswoman Christine Aime suggested that festival staff had made a mistake

"There is no specific mention about the height of the women's heels as well as for men's," Aime said of Cannes' dress code. "Thus, in order to make sure that this rule is respected, the festival's hosts and hostesses were reminded of it."

Some were already calling the incident "Shoegate." Asif Kapadia, the director of the Amy Winehouse documentary Amy, added on Twitter that his wife was also initially refused entry to his film's Cannes premiere Saturday because she wasn't wearing heels, but she was eventually allowed in.

The dust-up is particularly awkward for Cannes because this year's festival has been marked by considerable discussion about gender equality in the movie industry.

Sicario screens

When Sicario premieres at the festival, it will be the only Canadian-directed movie competing for the festival's prestigious Palme D'or. 

Villeneuve's drug-trafficking drama stars Del Toro, Brolin and Blunt as members of a government task force trying to take down the brutal head of a Mexican drug cartel. 

It's the first time the Quebec-born, Oscar-nominated filmmaker has had a movie in the festival's main competition.

The 47-year-old told reporters he's feeling "very proud."

"It's a big gift from the festival to invite us," he said. "Particularly for [Sicario], because it is a movie that I feel, from a cinematic point of view, very close to me. I did it without any compromise and total freedom, and the fact that it is being recognized on the other side of the ocean, it deeply touches me."

The Montreal  filmmaker is vying for the Palme d'Or against 16 other films, including Todd Haynes's Carol, Paolo Sorrentino's Youth, and Gus Van Sant's The Sea of Trees.

Fellow French-Canadian filmmaker Xavier Dolan is sitting on the nine-member jury which will vote on the winning film.

The chosen film will be announced at the closing ceremony on Sunday, May 24.

With files from CBC News