The minority Liberals and the NDP — who joined forces a mere month ago — are clashing over a pending vote on the budget bill, which has stalled in the legislature.
The minority Liberals have accused the NDP of blocking the legislation and breaking their vow to pass the budget.
But the New Democrats said they only agreed to allow the budget to pass its first hurdle in the legislature, so it could be debated and amended if necessary.
With the legislature set to rise June 7, there's little time left to implement key tax measures the NDP demanded, such as stopping a scheduled corporate tax cut on July 1 and hiking taxes for the wealthy.
Finance Minister Dwight Duncan also warned that if the budget isn't passed by the summer, the province's credit rating and plan to slay its $15-billion deficit will be in jeopardy.
NDP Leader Andrea Horwath offered a solution Thursday, saying she's prepared to fast-track the tax changes in a new piece of legislation separate from the massive 350-page budget bill.
But McGuinty, who crowed about his marriage of convenience with Horwath last month, said that wasn't part of the deal.
"We didn't come to the table with legal counsel," the premier said. "We didn't execute a duly notarized and witnessed contract in triplicate. But notwithstanding that, I feel we had an agreement."
He said he's confident Horwath is "honourable and trustworthy" — as far as their agreement is concerned — and will allow the budget to pass before the summer, if only to ensure her party's demands are implemented in time.
"So all we're asking the NDP to do is to honour an agreement which they entered," he said.
The premier's playing "make believe," Horwath replied.
"It's very clear that the government is trying to hold hostage these progressive tax measures and try to ram through the budget bill at the same time," she added.
"We think that is irresponsible. I've been clear from Day 1 that I want to see some scrutiny of that budget bill."
The party said it's concerned about changes to environmental protection rules and other measures that would allow for the privatization of public services.
But Horwath made it clear she's not looking to trigger an election by defeating the budget bill.
"You know the premier can stand there and say what he likes in terms of a conversation that happened, but he knows very well what needs to happen to move this process forward," she said.
"He needs to work with us. He can't go back to his same old way of doing things and saying it's my way or the highway, and then pointing fingers and accusing us of wanting to call an election."
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