Bids for a giant truffle that may get blessed by the Pope are expected to exceed $206,000 US at a weekend charity auction, media reports say.

The white, 1.5-kilogram fungal truffle will be put on the block in Florence on Saturday. Proceeds from the auction will go to an Italian organization that helps sufferers of genetic diseases, a group that helps street children in London, England, and Catholic charities in Macau.

The truffle was found in Tuscany by truffle hunter Cristiano Savini and his dog Rocco.

Organizers are hoping to have the truffle blessed before the weekend event. Auction organizer Giselle Oberti told Britain's Guardian newspaper: "We hope to get the truffle blessed by the Pope before it flies out, but things need to move fast, as white truffles should be eaten within 20 days."

Media reports say the largest truffle ever discovered weighed 2.5 kg and was presented to Dwight Eisenhower when he was U.S. president.

The Guinness World Records book lists a 1.3-kilogram white truffle found in Croatia in 1999 as the biggest.

With files from the Associated Press