A cocktail dress from the collection of Diana, Princess of Wales, and an ensemble worn by Princess Grace of Monaco to meet John F Kennedy at the White House, went under the hammer for 325,000 dollars (£256,000) each.

The high-profile fashion looks were sold as part of an auction titled Unstoppable: Signature Styles Of Iconic Women In Fashion at Julien’s Auctions in Los Angeles.

The Diana-worn black velvet dress with nautical inspired accent, designed by Catherine Walker and worn to a private event in 1993, far exceeded its estimate of 100,000 and 200,000 dollars.

It comes after a Jacques Azagury designed dress worn by Diana in Florence, Italy in 1985 set a new world record for the most expensive dress worn by the former royal at auction – selling for more than one million dollars in December.

Meanwhile a tweed green ensemble worn by the Academy Award winning actress Grace Kelly, from the golden age of Hollywood, also far exceeded its estimate of 60,000 to 80,000 dollars.

The US star, who would later retire from acting at the age of 26 to become the Princess of Monaco, wore the Givenchy outfit in 1961 with her husband Prince Rainier III to meet President Kennedy and First Lady Jacqueline Kennedy at the White House.

Other items which topped the sale include the three-tiered tutu worn by Sarah Jessica Parker in her Emmy award-winning role as Carrie Bradshaw in the opening credits of Sex And The City.

The tutu, found by Patricia Field who was the creative maven behind all the looks on the hit show, also far exceeded its estimate of 8,000 to 12,000 dollars, selling for 52,000 dollars (£41,000).

While a John Galliano for Christian Dior newsprint silk strapless dress, which became a fashion must-have when Parker wore a similar version on Sex And The City, sold for 11,430 dollars (£9,000).

The collection of high-profile outfits also included a Burberry trench coat worn by late pop star Whitney Houston to a Moroccan music festival in 2008, which sold for 4,550 dollars (£3,600).

Martin Nolan, co-founder and executive director of Julien’s Auctions, said: “This showstopping collection of exquisite garments adorned on the Royals, Princess Diana and Princess Grace of Monaco, and the street wear style tutu worn on Hollywood icon Sarah Jessica Parker that made fashion statements at the time of their appearances, are now a part of auction history.

“Today’s auction’s results amplify the value and collectability of these fashion looks that became some of the most iconic style moments of our time.”