Mulcair called the decision to proceed without Quebec short-sighted considering that Premier Pauline Marois appears poised to call an election.
"We find it a shame that Quebec is being left out of the agreement," the New Democratic Party leader told reporters after a speech to the Montreal Board of Trade.
"The federal government has to understand that Quebec has its own education system, its own specific role in manpower training and unfortunately this is going to play right into the next election here in the province. It's short-sighted on the part of the federal government to not have been able to reach an agreement on this."
The sovereigntist Parti Quebecois government has previously expressed its dissatisfaction with the program and wants to be able to opt out with compensation.
Federal Employment Minister Jason Kenney announced the deal at an annual networking conference of conservatives in Ottawa.
Kenney said he plans to have "productive" discussions with Quebec Labour Minister Agnes Maltais on the Canada Job Grant, which was a key part of the Tories' 2013 budget. He declined to say if opting out was on the table.
Nova Scotia has also expressed reservations about the deal.
The deal gives the provinces and territories more flexibility in how they fund the Canada Job Grant. They initially balked at taking their $300-million share from a federal transfer that funds job training for people who don't qualify for employment insurance.
Mulcair said the agreement recycles funds already sent to the provinces and is a waste of time and money.
He said the New Democrats are focused on job creation and he announced they will be conducting cross-Canada discussions with small- and medium-sized businesses about that.
In the meantime, he hopes the Conservatives work something out with Quebec on the Job Grant.
"It's an important missed rendez-vous by the Conservative government to have excluded Quebec from this deal," Mulcair said. "Let's hope they can get it right in short order."
_ With a file from Canadian Press reporter Lee-Anne Goodman in Ottawa
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