Disney film Muppets Most Wanted, starring Tina Fey and Ricky Gervais, features the characters on a mayhem-hit grand tour of Europe.
Miss Piggy, who dons the ivory couture wedding gown in the movie, has been trying to convince Kermit the Frog to marry her for years but film bosses have kept schtum on whether fans will see them finally manage to tie the knot.
"Vivienne Westwood is fabulous-just like moi," said Miss Piggy.
"When I asked her to design this wedding dress for moi's new movie..., she was thrilled and I was thrilled. The only one a bit 'iffy' about it was the frog."
The gown, teamed up with an ivory tulle veil, has "corset detailing and paillettes made from recycled plastic bottles".
British designer Westwood spoke about the gown in the March issue of US Harper's Bazaar.
She said: "The dress is one of my favourite styles. It's called the Court dress and is inspired by 17th Century English royalty and the court of King Charles II.
"It has been designed especially ...in a white pearl sequin fabric made from recycled water bottles. It's the perfect choice for a royal sow."
Muppets Most Wanted, directed by James Bobin, hits UK cinemas on March 28.