Australian supermodel Elle Macpherson is giving one lucky fan the chance to enjoy a tea time date with her for charity.

The beauty has offered up the eBay.com auction prize to raise funds for the Sierra Club Foundation, which provides environmental education.

MACpherson will meet with the winner in London or New York City, and she has taken to her Twitter.com page to encourage fans to bid on the lot before the sale ends on 28 April (13).

In a post, she writes, "Don't forget to bid on eBay... for a hang out with me in aid of the Sierra Club Foundation."