Mayor Brian Bowman says the Manitoba government is trying to wriggle out of a commitment to pay for its share of a $467-million project rapid-transit project that's already underway.

The Progressive Conservative government said Tuesday that the province wants to amend the terms of an agreement to fund the second phase of the Southwest Transitway and widen Pembina Highway below the Jubilee Avenue underpass.

The city and province each agreed to cover $225 million of the tab when the total project cost was estimated to be $587 million. Ottawa agreed to pay for the rest of the project.

The cost of the project was reduced in 2016 after a more detailed design was completed. Now the mayor said the government is attempting a renegotiation and has not provided funds as promised.

"There is a desire by the provincial government to create a new agreement to amend the current agreement in a way that is less favourable to the City of Winnipeg and city of Winnipeg taxpayers. Obviously I don't support that. I'm expecting them to honour the commitment they made," Bowman said at city hall following an executive policy committee meeting.

Bowman, a non-practising lawyer, said he expects the province to honour "a fully executed" legal agreement.

"It wasn't executed by the previous provincial government. It was executed by Minister [Eileen] Clarke and this current provincial government," he said.

"We expect, especially given the fact we're currently building the second phase of rapid transit, that that contribution agreement will be honoured."

Mayor Brian Bowman says the Manitoba government is trying to wriggle out of a commitment to pay for its share of a $467-million project rapid-transit project that's already underway. 1:48

Bowman said the dispute with the province involves contingency funds. The mayor said he could not specify the dollar amount in question.

Caitlin MacGregor, a spokesperson for the PC government, said contingency funds are not eligible for funding under a federal program that pays for public-private partnerships such as the transitway deal.

As a result, the province's desire to amend the deal stems solely from the change in project cost from $587 million to $467 million.

"The federal government has also amended their agreement with the city to reflect the revised scope and funding contribution towards the revised project scope," MacGregor said in a statement.

"Manitoba is unable to provide reimbursement for project costs incurred until the amendment is fully executed and all supporting documentation is submitted to the province."

Bowman confirmed the province has held back money but would not say how much.

A report to council's finance committee this week says the province is behind on a total of $54 million worth of commitments to build municipal infrastructure.