Crusading actor Robert Redford has lavished praise on younger Hollywood stars including LEONARDO DiCAPRIO and Cameron Diaz for their charity efforts.

The veteran campaigner and political activist is impressed by the efforts of the younger generation to champion environmental causes, but fears the majority of Hollywood starlets simply manipulate charities for cheap publicity stunts.

He says, "You've got Leonardo DiCaprio, Cameron Diaz. There's a few actors out there that are working in smaller areas.

"But there is a tendency in Hollywood to be fickle about your commitments. Then it becomes a question: is this commitment coming from an ego, when the actor says, 'I want to be taken seriously, so I'm going to attach myself to a cause,' and it lasts for about a year?"