Clare Waight Keller has resigned as creative director of Pringle of Scotland.
The designer - who is pregnant with her third child - has been at the label since 2005 but has now decided to leave as she believes the time is right to move on.
She said: "It's a sad moment - but the perfect time to close my era at Pringle. I leave incredibly proud of Pringle's growth from a Scottish knitwear company to an international luxury brand. And to a certain extent, this move is for personal reasons."
Douglas Fang, a member of the family that owns Pringle, added to WWD: "Clare's unique understanding of knitwear and design talent allowed her to modernise the image of Pringle, while remaining true to its heritage. Clare will be greatly missed."
Clare took over at Pringle of Scotland in 2005 after being a senior womenswear designer at Gucci, under Tom Ford, following spells at Ralph Lauren's Purple Label men's line and Calvin Klein.
Her replacement at the brand - whose latest campaign was fronted by Tilda Swinton - is yet to be announced.