French cinemas were right to object to Netflix' appearance at Cannes, the film festival's director said on Tuesday, ahead of the movie fortnight that this year has been marked by a fight between theatres and the U.S. online giant.

Netflix, which streams films and television shows to subscribers, has two of the hottest movies in contention for the Palme d'Or - its first time in competition at the festival that France boasts is the greatest in the world.

But, in a country where movies shown in cinemas cannot be streamed for three years, Netflix refused to arrange distribution across France - meaning "Okja", starring Tilda Swinton and Jake Gyllenhaal, and "The Meyerowitz Stories", with Ben Stiller and Dustin Hoffman, will not be seen on the big screen after their Cannes premiere.

The outcry from French cinemas was such that there were rumours the two movies would be excluded at the last minute.

That has not happened, but the festival has tightened its rules so that in future any in-competition film will have to get a theatre release - effectively barring Netflix after this year.

"Cannes is a film festival in theatres, and, for the territory of France, we would like to have all the films competing in Cannes available in theatres," festival director Thierry Fremaux told Reuters in an interview.

"Netflix decided to go first via the internet, so French theatres protested, and they are right, because cinema is first of all in theatres."

Netflix has not responded to requests for comment but CEO Reed Hastings said on his Facebook page: "establishment closing ranks against us". He added that "Okja" was an "amazing film that theatre chains want to block us from entering into Cannes film festival competition."

Fremaux says the Netflix titles were short-listed - despite the company's well known business model - for their artistic merit, "directed by two directors who are real movie guys": the Korean Bong Joon-ho and American Noah Baumbach.

When asked whether Cannes risked missing out on new ways of movie-making, Fremaux said he wanted to talk about the movies, not the "Affaire Netflix" which has grabbed the headlines.

"The festival is always changing and is always the same," he said.

"The only thing, as we are talking about movie theatres, is that at a certain moment in the day, several times a day, the lights go out and we watch a film – together – and that’s cinema."