Ahead of a talk at Clunes Booktown Festival, Bob Brown joins the Breakfasters team in studio to share his thoughts on Australia's potential to have impact on the environment and aiding in attempts to encourage international peace.

His talk, titled Defiance and Optimism is in conversation with broadcaster Hilary Harper, will be held at Clunes Town Hall, Saturday 21 March.

He talks about his hopes to encourage more activism and resistance in Australia, dismissing notions that Australian's don't have power at an international scale.

"Making our own society better, protecting our environment and reaching out and helping people elsewhere in the world. A country that gives less than a third of its due to overseas aid these days - that's Australia."