Steven Guilbeault to announce resignation as member of Parliament on Wednesday

Former cabinet minister Steven Guilbeault is set to resign as a member of Parliament, sources have told The Canadian Press.

Guilbeault is expected to inform the Liberal caucus on Wednesday.

Guilbeault has become increasingly disillusioned in recent months by what he has called the dismantling of climate policies under Prime Minister Mark Carney.

He quit Carney's cabinet last year after Ottawa's energy deal with Alberta was made public.

In a media statement, he said he strongly opposed the agreement between Ottawa and Alberta and called the proposal to exempt Alberta from clean electricity regulations "a serious mistake."

He wrote that "several elements of the climate action plan I worked on as minister of the environment have been, or are about to be, dismantled: the consumer carbon pricing, the zero emission vehicle standard, the oil and gas sector emissions cap, the framework to eliminate fossil fuel subsidies, and the clean electricity regulations."

Since then, he has publicly criticized his own government's approach to climate policy.

Responding to media reports stating Guilbeault was set to resign, federal ministers Lena Diab and Marjorie Michel showered the former environment minister with praise.

Michel, who was holding a press conference on Parliament Hill about the Ebola outbreak in Africa on Tuesday, said Guilbeault was a "fantastic" colleague.

"I really appreciate his work, his advocacy, and I'm fully respectful of his decision," she said. "At the same time, I have complete faith in what our government is doing."

Diab said in French that Guilbeault was an excellent minister and member of Parliament.

Guilbeault has represented the Montreal riding of Laurier-Sainte-Marie since 2019.

Guilbeault has often said his activism began at age five, when he climbed a tree in an attempt to stop real estate developers who were clearing forest near his home in La Tuque, Que.

In 1993, he co-founded Équiterre and helped it become the largest environmental organization in Quebec. He was its senior director from 2007 to 2018.

Before politics, he also worked with Greenpeace, Deloitte and Copticom.

Guilbeault was one of two Greenpeace activists arrested in 2001 for climbing the CN Tower in Toronto — then the world's tallest building. The two activists unfurled a banner from the observation deck in an attempt to draw attention to climate change and protest the decision by the Canadian and American governments not to ratify the 1997 Kyoto accord.

International Trade Minister Maninder Sidhu told The Canadian Press Tuesday that he has "tremendous" respect for Guilbeault and his work. 

"Our conversation will continue on the environment," he said.

This report by The Canadian Press was first published May 26, 2026.

By The Canadian Press | Copyright 2026, The Canadian Press. All rights reserved.