Photo: All rights reserved.

The blue velvet gown Diana, Princess of Wales wore when she famously enjoyed a dance with John Travolta at the White House is expected to fetch $452,000 at auction.

The late British royal donned the stunning Victor Edelstein dress back in 1985 to attend a state dinner hosted by then-U.S. President Ronald Reagan and his wife Nancy in Washington, D.C., and hit the dancefloor with fellow guest Travolta.

The off-the-shoulder designer outfit had initially been offloaded at a charity auction in New York in June, 1997, just two months before Diana's death in Paris, France, and it was sold to the highest bidder again in 2013 as part of a collection of the princess' gowns.

Now it's going back under the hammer at London's Kerry Taylor Auctions, where experts predict the dress will be a big hit with buyers once more.

Sale representative Lucy Bishop says, "This is arguably her most iconic gown, the photos of her being twirled around the dance floor by a handsome John Travolta at the White House caused a sensation at the time, and are still memorable today.

"Royal protocol required her to dress very demurely - however this gown is very evocative of 'old Hollywood glamour', quite low-cut and falling off the shoulders. It was a bold and mature choice for such a young princess, and she wowed everyone on the night.

"The estimate reflects Diana's enduring appeal to private collectors and museums internationally."

The auction is set to take place next month, reports the Daily Mail.