The 36-year-old spent 12 years in Formula One, winning nine races and twice finishing third in the championship.
Webber decided to leave the competition for German company Porsche's new sportscar programme, which could include an attempt at Le Mans 24 Hours, despite having options to stay in Formula One, both with Red Bull and other teams.
"Porsche has written racing history as a manufacturer and stands for outstanding performance and technology at the highest level," he said on his website (www.markwebber.com).
"I'm very much looking forward to this new challenge after my time in Formula 1. I can hardly wait to pilot one of the fastest sports cars in the world."
Image: Mark Webber
Photograph: Mark Thompson/Getty Images
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