The departure of Steven Guilbeault, the Liberals' face of climate, has sparked a question among fellow progressives.

He is expected to formalize the announcement in a speech in the House of Commons on Wednesday afternoon.

Guilbeault's anticipated departure comes in the wake of Mark Carney's climate policy concessions to Alberta and its oil and gas sector.

OTTAWA - Former environment minister and staunch environmentalist Steven Guilbeault confirmed Wednesday he will step down as a Liberal member of Parliament this summer.

The former environment minister confirmed widely reported rumours with a social media post Wednesday, saying he would be resigning his Montreal seat this summer.

The departure of Steven Guilbeault, the Liberals' face of climate, has sparked a question among fellow progressives.

Liberal MP Steven Guilbeault said he wouldn't rule out returning to federal politics under a different prime minister.