Matthew Williamson is launching a diffusion line.

The British designer - whose styles are often seen on the likes of Sienna Miller and Cat Deeley - is creating a range with Italian company the Mariella Burani Fashion Group, in a move which he believes couldn't be timed better.

He said: "It will be womenswear but all will be revealed in due course - watch this space.

"It just felt right - we've been here for 13 years and it's time to take the label further. We're ready for it now."

Asked what the collection would encompass, he explained: "That's a good question, it's still being worked on at the moment. I'm just a workaholic - I just needed even more to do."

The label's chief executive Joseph Velosa believes the new clothing range will be seen in a similar way to Marc by Marc Jacobs and See by Chloe.

He added to "It will carry all the essence of the Williamson woman but it'll be for her younger sister and at a lower price point. We've been around for a long time and this is the next step."

The collection is due for release in February 2011.

Matthew recently revealed he had his celebrity fans to thank for his 13-year career because they proved different Women could wear his creations.

He said: "I think there have been about three women in my career: Valentine, Jade Jagger and Sienna Miller. They're all very different, but I think you need that - to be able to build a brand that's multi-faceted."