Heidi Klum and Thandie Newton will auction their dresses online to raise cash for charity next month.

The outfits will be modelled at London's Sketch at the end of the month before being placed on sale on eBay.

In total 27 celebrity dresses will be sold, marking the opening of Katherine Heigl's new movie 27 Dresses.

All money raised will go to the Lavender Trust. The auction begins on March 4 at 7pm.