Maisie Williams wants to help more brands be sustainable.

The former 'Game of Thrones' star admitted there are some firms she refuses to work with because of their negative environmental impact, but she thinks it has a bigger effect if she introduces new projects to a company rather than only agreeing to team up with firms that already share her values.

Speaking to Jessie Ware on her 'Table Manners' podcast, she said: "There are some brands that I won’t work with but I also feel like what I kind of feel like makes more of an impact is to work with a brand that isn’t necessarily the most sustainable and find a project where they can be sustainable.

"So I’m doing a thing with a brand called Coperni and they aren’t necessarily known to be a sustainable brand, they’re a pretty boutique brand so it’s not mass-produced and everything that they do is really high quality but it’s not necessarily sustainable.

"So we’re working together on their first ever completely sustainable handbag and I think that makes more of an impact than just working with a completely eco, entirely ocean, because it becomes a bit of an echo chamber where the only people who know about that are the people who want to live their life that way and it doesn’t ever really reach anyone who’s not doing that already.

"So although I say there are brands that do need to do more, I kind of hope that maybe I could work with those brands and maybe we could do something that is different."

The 24-year-old star works with high street retailer H&M and is proud of their efforts to be more sustainable.

She said: "I’m their sustainability ambassador basically, and so they have a couple of goals that they want to achieve, they want to be 90% sustainable by 2030 but I feel like they’re kind of already on the way there.

"At the moment I think, I’ve not brushed up on my numbers, but at the moment they’re sort of maybe 40% across the brand using more sustainable and recycled materials, H&M group have been investing in a lot of new technologies where they don’t just find a sustainable fabric but they take old fibres, they smash them down and they grate them up and they turn them into a new woven denim.

"That’s really great because not only is it a sustainable material but you’re getting rid of the problem because we still have all these clothes on the planet."

Listen to the episode at https://play.acast.com/s/tablemanners/