Alberta’s proposal to leave the Canada Pension Plan (CPP) could cause “serious harm” to working people and retirees, Ontario’s finance minister said in an open letter published Wednesday.

Peter Bethlenfalvy addressed the letter to Deputy Prime Minister and Finance Minister Chrystia Freeland and called for an “urgent” meeting to discuss the proposal with Canada's federal, provincial, and territorial finance ministers

“While we will always maintain our respect for Alberta, our government firmly supports the CPP and shares your serious concerns with Alberta’s proposal to withdraw from it,” Bethlenfalvy wrote.

Hours after the letter was released, Freeland agreed to convene a meeting with the finance ministers to discuss Alberta's plan to withdraw from CPP.

Speaking in Calgary, Freeland said any province has the right to leave the program, but it's important that the decision “be based on facts and be clearly and well informed.”

“It is absolutely my conviction and the federal government's conviction that the CPP works really, really well for all Canadians, for all Albertans, and I am looking forward to the opportunity to discuss that further with the finance ministers of all the provinces and territories in the days to come,” she said.

Bethlenfalvy's letter comes after Alberta Premier Danielle Smith released a third-party report last month that suggested the province will be entitled to $334 billion by the time it leaves the CPP in 2027 -- more than half of the fund's assets -- and said public feedback would determine the need for a referendum.

For its part, the Canada Pension Plan Investment Board has estimated Alberta is owed about 16 per cent of the fund.

Since 2020, Smith's United Conservative government has argued that Albertans are paying disproportionately into CPP and said it would get a better deal if it developed its own pension plan.

The latest developments have drawn the ire of Employment Minister Randy Boissonnault, who called the proposed plan "flawed" while speaking to reporters on Wednesday.

"The overwhelming number of Edmontonians and Albertans that are writing to me are saying: please tell Premier Smith hands off my pension," the Alberta MP said on his way into a Liberal caucus meeting on Parliament Hill. "I think the best place for this conversation to take place is at the next Council of the Federation. I think the premiers need to have it. I am confident that finance ministers will have this conversation."

Previously, Boissonnault told CTV’s Question Period host Vassy Kapelos in an interview that aired Sunday that if Alberta chooses to leave the plan, its decision to do so would be final.

“If Albertans decided a referendum to pull out of the CPP, they will be able to do that, but it's a one way ticket,” Boissonnault said at the time. “You don't get to come back, that's also very clear in this legislation."

Prime Minister Justin Trudeau also weighed in on the topic, saying: "Alberta's withdrawal would weaken the pensions of millions of seniors and hardworking people in Alberta and right across the country. The harm it would cause is undeniable."

If Alberta does exit the pension plan, Bethlenfalvy said the CPP fund would need to be “divided fairly” among the remaining members while “acknowledging the contributions made by workers in each participating province and territory.”

Bethlenfalvy said the Ontario government would also welcome a “rigorous analysis” of the assumptions that Alberta’s proposal is based on.

With files from CTV News Parliamentary Bureau Writer Spencer Van Dyk and The Canadian Press