If the government doesn't make good on pharmacare legislation by March, that would kill the Liberal-NDP political pact, New Democrat Leader Jagmeet Singh said Wednesday.
But he made it clear that any collapse in the deal, which is meant to hold off a federal election until next year, would be the Liberals' fault.
Singh has been talking tough this week about the looming deadline to table a bill, and met with the prime minister Monday to lay out his expectations.
"It was a tough meeting," he said. "I made it clear that this is something we're very serious about. We're not going to extend this any further."
Reporters lobbed questions at Singh Wednesday about what consequences he's willing to bring down on the Liberals.
He said if the government doesn't deliver a bill by March 1, that would mean the Liberals are turning their backs on the parties' agreement.
The deal originally said a bill should be passed by the end of 2023, but after months of negotiation over what the legislation should say, the two parties punted the due date.
The Liberals and the NDP originally struck their deal in 2022, months after Prime Minister Justin Trudeau was elected with a minority mandate for a second time in a row.
In the so-called supply-and-confidence agreement, the NDP promised to support the minority government on key votes in exchange for movement on shared priorities, including pharmacare.
The agreement only calls for "progress toward a universal national pharmacare program," and offers no other specifics.
Singh told reporters Wednesday that the parties have fundamental differences of opinion about how that should actually work.
The NDP is looking to see legislation that would underpin a future universal, single-payer system, and the grassroots of the party voted at a policy convention in October to settle for nothing less.
The Liberals, meanwhile, have pushed for a model that would serve people who don't have existing insurance coverage, Singh said of the discussions.
Health Minister Mark Holland has said little of the inner workings of the negotiations, except to say they are "progressing concretely."
"The challenge on these things is that as you get closer to thinking you have an agreement there are always additional details and additional pieces that come into play," he said Tuesday.
Cost is also a factor, he said.
"We can't afford this to be a massively expensive program. We're not in a time when the fiscal framework can absorb massive costs."
Singh said he told the prime minister there would be repercussions for missing the pharmacare deadline. But he wouldn't tell reporters Wednesday what the consequences would be.
If the deal does fall apart, that doesn't mean the NDP will necessarily bring down the government.
Since the agreement was struck, polls have shown the Opposition Conservatives rising in popularity across the country under the leadership of Pierre Poilievre.
That leaves the Liberals and NDP at risk of losing seats the next time Canadians go to the polls.
They can hold one off until fall 2025 at the latest, when a vote must take place according to fixed election date law.