Greta Gerwig has insisted there's no rivalry between 'Barbie' and 'Oppenheimer' - and has urged film fans to see both at the cinema.

The 'Ladybird' director's new movie - which stars Margot Robbie as the iconic doll - is going up against Christopher Nolan's nuclear new drama 'Oppenheimer' when they are both released on the same day on July 21 but Gerwig is adamant the two summer blockbusters - known collectively as 'Barbenheimer' - both deserve to be seen on the big screen.

She told The Hollywood Reporter: "It’s all love — double up, double up twice. I think you’ve got to see what the experience is, Barbie then Oppenheimer, Oppenheimer then Barbie. I think you’ve got to take all of the journeys."

Issa Rae - who plays President Barbie in Gerwig's film - also weighed in on the box office battle, calling it "hilarious". She added: " I love that there’s solidarity though where people tried to pit us against one another but now it’s turned into like a double-feature situation. Obviously you should see 'Oppenheimer' first and then cleanse your palate with 'Barbie' ...

"['Oppenheimer'] is about an atomic bomb, people are gonna die. I want to end my weekend, I want to have mimosas and drinks and cocktails after Barbie, I don’t want to like sulk. That’s just my plan, as long as you’re seeing 'Barbie' I don’t care."

The pair were speaking at the 'Barbie' world premiere in Los Angeles on Sunday (09.07.23) and also in attendance was actress America Ferrera, who filmed rollerblading scenes with Margot for the movie - and she insisted she was blown away by the world Gerwig created.

She said: "It just evoked a deeper childhood nostalgia for imagination and play and beauty and I just got emotional, I started crying. The world Greta created is just unbelievable; she’s such a visionary."