It's the first opportunity for the opposition parties to bring down the minority Liberals, sending voters to the polls for a second time since last fall's Oct. 6 election.
The Liberals need at least two opposition votes to survive and have yet to strike a deal with the NDP. But they can't put it off any longer, as the rules of the legislature require that a vote on the budget motion be held no later than April 24.
The Progressive Conservatives have already vowed to vote against the budget, saying it does nothing to create jobs or stop the province from spiralling further into debt.
Government house leader John Milloy said he'll continue to work with the New Democrats, but made no promises to compromise to avoid another election.
"Coming back from a break week, I had everyone asking me, 'Reassure me that there won't be an election'," he said Monday. "I can't give that reassurance."
The NDP want to hike taxes for anyone making more than $500,000 a year, which they say will allow the province to lift a planned freeze on welfare rates and put more money into home care and community care.
They also want a new job creation tax credit, the provincial portion of the HST removed from home heating bills and Ontario Northland railway to remain in public hands.
Premier Dalton McGuinty has poured cold water on the NDP's demands, claiming they'll add $1 billion a year in spending when his government is trying to slay a $15.2-billion deficit.
NDP Leader Andrea Horwath fired back in the legislature Monday, saying McGuinty "knows very well that New Democrat proposals will not add one red cent to the deficit."
If a deal isn't reached within the next week, the NDP could buy more time by supporting the budget or abstaining from the April 24 vote. That would allow them to put off their final decision until a second confidence vote on the budget legislation is called.
All three parties are still mired in campaign debts, which will likely weigh heavily on any decision that could result in another election.
Horwath wouldn't reveal the NDP's game plan, saying she remains optimistic that an agreement can still be reached before the vote next Tuesday.
"We'll use up every minute that we can to get to a place where we can see a budget that's more balanced and more fair for Ontarians," she said.
Milloy wouldn't say whether the Liberals would be prepared to accept any of the NDP's suggestions, saying he's leaving those negotiations behind closed doors.
"We're certainly not there yet because our analysis shows their suggestions will add to the deficit," he said.
Instead, he accused the Tories of forcing another costly election that no one wants — a familiar refrain from the Liberal camp in recent weeks — by nominating candidates in various ridings.
However, Milloy acknowledged that he's talked to his riding association and campaign staff about "contingencies."
Tory Leader Tim Hudak said he asked to have nominated candidates in place before December. The party's new president, Richard Ciano, has also made it clear that he wants to strengthen local campaigns and riding associations before the next election.
"We want to have early nominations of folks in place, because when you're in a minority government, you never know," Hudak said.
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