Former Liberal leader Stéphane Dion, seen at the Liberal leadership convention in Vancouver in May 2009, has been released from a Mexican hospital.Former Liberal leader Stéphane Dion, seen at the Liberal leadership convention in Vancouver in May 2009, has been released from a Mexican hospital. (Adrian Wyld/Canadian Press)

Former federal Liberal leader Stéphane Dion has been released from a Mexican hospital after a severe case of food poisoning, his office says.

Dion was scheduled to speak about climate change negotiations at a conference in the Mexico City area on Monday when he started feeling ill, his staffer Nicole Ng Yuen said.

He is scheduled to return to Canada later Wednesday, she added.

"He's been released and is feeling much better," Ng Yuen said.

A member of Parliament since 1996, Dion was replaced by Michael Ignatieff as Liberal leader in December 2008 after a dismal election showing for the Liberals, followed by Dion's failed attempt at replacing Prime Minister Stephen Harper's minority Conservative government with a Liberal-NDP coalition, with the signed support of the Bloc Québécois.

During his tenure as environment minister in Paul Martin's government, Dion was widely credited for his steering of the 2005 UN conference on climate change in Montreal.

At the summit, delegates agreed to extend the life of the Kyoto Protocol beyond its 2012 expiration date and negotiate deeper cuts in greenhouse-gas emissions.

This week's conference in Mexico was a lead-up to the UN climate change summit in Cancun next month.

With files from The Canadian Press