Guess who’s become the most vocal critic of Prime Minister Justin Trudeau’s federal carbon tax? Brace yourselves: the NDP.

The first attack came from NDP leader Jagmeet Singh. He supported the Liberal carbon tax in the House of Commons, and sang its praises to the highest mountain top. Singh isn’t singing from the same political songbook any longer, however. He dropped his support for Trudeau’s pet project last week like a bad habit. The NDP leader now desires a policy that won’t “put the burden on the backs of working people, where big polluters have to pay their fair share.” His party will release its own plan in a few months’ time.