Greta Gerwig insists that the Birkenstocks featured in 'Barbie' were not product placement.

Greta Gerwig did not include Birkenstocks in Barbie for product placement

Greta Gerwig did not include Birkenstocks in Barbie for product placement

Margot Robbie's title character is unexpectedly seen in the sandals towards the end of the movie and the filmmaker insists that this was not done for commercial purposes.

In an interview with Variety alongside the hit film's costume designer Jacqueline Durran, Greta said: "I will have it be known, that the Birkenstocks was not product placement. We just wanted Birkenstocks."

The 'Little Women' director explained how the shoe embodies the changes that Barbie goes through during the picture.

She said: "When she first holds the shoe up, it's the classic suede version. As she becomes more human, there are a lot of things - the clothes, the fabrics, the patterns, and even the jewellery become more delicate. That's something Margot and Jacqueline did.

"But the Birkenstock at the end shows how Barbie changes from beginning to end. We wanted it to be pink because she's still Barbie. We looked at the bright pink one.

"It felt sweet, charming and perfect. Anything on screen, I feel we looked at 100 versions of."

Gerwig and Durran explained how a scene involving bathing costumes required lots of work as the 40-year-old director wanted swimwear items that resembled those worn in the past.

She said: "I didn't want them in string bikinis. I wanted something more 1950s or 1920s bathing costumes."

Durran added: "In the art department, they had boards and boards of reference. They had 1950s photographs of groups of women playing on the beach.

"What was interesting was groups of women playing with beach balls. They were nostalgic and had an innocence about them. It was groups of women doing things on the beach and it wasn't objectified in any way."