Sienna Miller will be launching a fashion label along with her sister Savannah, it was revealed today. It will be called Twenty8Twelve and it’s to be backed by Pepe Jeans owner Carlos Ortega. Twenty8Twelve will feature denim, knitwear, tailored jackets, dresses and outerware.

‘We wanted to created that London world that feels inaccessible,’ said Sienna, while highlighting her inspirations, which include the poetry of the Beat generation, Patti Smith and the dark and brooding London of Dickens.

“I’ve always loved fashion, and Savannah got a First in design at Saint Martins. We hadn’t thought to pursue it together, but this just happened organically. And setting up a label with your sister is a lot of fun — there haven’t been any fights yet.”

“I’m not about to become a brand,” Sienna explained. “Because of my job, people are willing to invest in the business, but my sister’s an incredible designer, and it’s a great opportunity for me to work with her.”

The name of the fashion label is made up from Sienna’s date of birth – the actress turned 25 on 28 December.