Britney Spears and Paris Hilton.

Britney Spears and Paris Hilton have been named the worst dressed celebrities¹ of 2006, according to an annual list from US fashion critic "Mr. Blackwell."

The poison-penned arbiter² of style described newly single Spears and celebrity³ socialite Hilton as "two peas in an over-exposed pod! Style-free and fashion deprived."

Spears and Hilton have been regularly photographed together enjoying nights out on the town in the wake of Spears' divorce from husband Kevin Federline.

Some of Blackwell's nastiest words were reserved for Camilla , the wife of Prince Charles, who finished No. 2 on the list.

"The Duchess of Dowdy⁴ strikes again," wrote Blackwell. "In feathered hats that were once the rage, she resembles a petrified⁵ parakeet from the Jurassic age. A royal wreck⁶."

Party-loving teen idol⁷ Lindsay Lohan was next, with Blackwell saying her dress sense had gone from "adorable to deplorable."

Christina Aguilera was also in Blackwell's fashion hall of shame. He called her a "dazzling singer" but added that she "puts good taste through the wardrobe wringer . All crass⁸ and no class."

He referred to Mariah Carey as "Mariah the fashion pariah⁹ ... the queen of catastrophic kitsch," and "American Idol" judge Paula Abdul as "a fallen fashion idol."

Blackwell did have some kind words, however, praising British actress Kate Winslet, Angelina Jolie, Beyonce and Katie Holmes for their sense of style.

Fashion critic Blackwell has issued his "ten worst-dressed women of the year" awards annually¹⁰ since 1960.