The 'Twilight' star auctioned off two "pecks on the cheek" at the star-studded amfAR charity benefit at the Cannes Film Festival.

The 23-year-old actor was sitting at a table with Domenico Dolce and Stefano Gabbana at the lavish Hotel du Cap when movie mogul Harvey Weinstein suggested Pattinson sell a smooch.

A fellow partygoer said: "Harvey joked from the stage that his daughters changed their last name to Pattison after they saw 'Twilight'.

CLICK HERE TO SEE PICS OF ROB FROM THE AUCTION!

"Harvey then suggested auctioning off an opportunity for someone's daughter to meet and get a kiss on the cheek from Pattinson. There were two bidders who paid £20,000 each for their daughters to have that kiss."

Rob was shocked by the impromptu auction, but agreed to take part to raise money for charity. What a good sport!

A source said: "Harvey put him on the spot, in a playful way. And Robert agreed to it in his usual brooding, modest way."

The proceeds will go to amfAR, an international foundation for AIDS research.

CLICK HERE FOR MORE ROB IN CANNES PICS!

Joshua Jackson, Diana Kruger, Josh Hartnett and Danny Glover also donated items, including a saxophone donated by former US President Bill Clinton, which sold for $130,000.