The group recently launched its first-ever Vegan Fashion Awards, and Paul MCCartney's daughter landed the honour for Most Stylish Women's Shoes, while Westwood picked up the prize for Most Stylish Handbag.
British actress Sadie Frost and socialite Meg Mathews were judges, and Jude Law's ex-wife admits she was impressed with the winners' efforts.
Frost says, "My two greatest passions are fashion and helping animals, so I was thrilled when Peta asked me to help judge their fashion awards. It's phenomenal how many retailers and top designers are using pleather, micro-suede and faux cashmere in their collections, and the quality is amazing. The new fabrics are kinder not only to animals but also to the environment."