The iconic pumps, one of four pairs worn by the actress when playing Dorothy Gale in the beloved 1939 movie, is one of the most popular attractions at Washington D.C.'s Smithsonian National Museum of Natural History.

However the sequinned slippers, which were a sparkling red when they were created for the film almost 80 years ago, have turned a dull reddish brown.

And Smithsonian bosses have now launched a campaign on fundraising website Kickstarter to pay for a $300,000 (£244,011) restoration program.

The money will also fund a new display case for the shoes designed to slow their deterioration, with a plan in place for them to take pride of place in a new exhibition on American popular culture due to open in 2018.

"This particular pair of ruby slippers really belongs to the American people, and so we thought as we sought support that we would invite the public to join us on this journey to help preserve them for the next generation," museum spokeswoman Melinda MAChado tells the BBC.

The shoes' condition has deteriorated because their sequins are made of plastic coated gelatin, and their red colour has faded because the plastic has flaked off.

In addition to the shoes displayed in the Smithsonian, three other pairs of ruby slippers used in the film are known to exist.

One is owned by Los Angeles collector David Elkouby, while another was bought for the Academy of Motion Picture Arts and Sciences in 2012 by benefactors including Steven Spielberg and Leonardo DiCaprio after they were auctioned by their previous owner, the actress Debbie Reynolds.

The other pair is unaccounted for having been stolen from The Judy Garland Museum in Grand Rapids, Minnesota in 2005.

In 2015, editors at the Associated Press reported an anonymous donor had put up a $1 million (£810,000) reward for information about the stolen slippers.