George Clooney has pledged $17,000 to watch his ex-girlfriend jump out of a plane. Sounds like charity sadism to me.

The Ocean’s 13 star has donated the money to Lisa Snowdon’s double charity parachute jump attempt, pushing her way past her original target of raising $7,000 for two children’s charities.

A source revealed, “George was so impressed with Lisa’s guts and determination that he wanted to help. Lisa had no idea how generous he would be until she logged onto her website and saw how much he put down.”

Model-and-TV host Lisa had an on/off relationship with George between 2004 and 2006, but they have remained friends ever since.

Lisa admits she is nervous about doing the two separate jumps for Shooting Star Children’s Hospice and Help a London Child, on her fund-raising page: “I’m a little bit nervous, especially about doing this twice (I don’t even know if I’ll enjoy the first one!) but knowing how much this will benefit both of these charities will really help me.”

Although the pair are on friendly terms, it seems unlikely George, 48, and Lisa, 38, will rekindle their romance. He is currently dating Italian TV presenter Elisabetta Canalis.