TORONTO - More opposition changes to the Ontario budget Monday were not enough to trigger a summer election, despite warnings from Premier Dalton McGuinty.

The New Democrats and Progressive Conservatives teamed up at finance committee to eliminate a key budget section on labour arbitration — even after McGuinty said Sunday he would not tolerate any more major amendments to the minority government's fiscal plan.

NDP Leader Andrea Horwath had warned the government the party would try to eliminate portions of the budget dealing with arbitration, said Finance Minister Dwight Duncan, who fills in as Liberal spokesman when McGuinty doesn't want to enter the battle himself.

"In response to the premier’s request this weekend, Ms. Horwath did provide notification, in writing, to him that these would be the last of the schedules she would oppose," Duncan said in a release Monday evening.

"Given the need to hold Ms. Horwath to her word, I will continue to keep a close eye on the committee tomorrow."

There are dozens of schedules attached to the omnibus budget bill that amend other pieces of legislation, which the opposition parties say should be stand-alone bills. McGuinty has said he will re-introduce some of them in the fall in new legislation.

The Liberals said they twice made concessions, including adding a new tax on the rich, to get the NDP to allow the budget to pass, and no longer trust the New Democrats unless they get written guarantees.

"I remain disappointed that Ms. Horwath continues to backtrack on the original agreements," added Duncan.

The Liberals also lashed out at the Tories for teaming up with the NDP to eliminate the section on labour arbitration, comparing the Conservatives to spoiled children.

"It’s like they asked for chocolate ice cream. We gave them chocolate ice cream, now they’re spitting it out," Liberal Yasir Naqvi told the committee. "It defies common sense, and I’ll let the public decide what’s going on here."

The Tories said they voted to defeat the arbitration section because it would lengthen timelines for decisions, and it doesn’t require arbitrators to take into account the employers' ability to pay.

McGuinty had warned the New Democrats in a letter Sunday to stop making major changes to the minority government's budget if they wanted to let it pass, as promised, and avoid triggering another election.

Horwath responded early Monday by saying she was always committed to seeing the budget pass, but wouldn't bow to McGuinty's demand that there be no more changes.

"I am not someone who responds to ultimatums by simply snapping to attention and doing what Mr. McGuinty says I have to do," she said.

"What I do is take a look at what the options are and try to find the path forward, and that’s exactly what I’ve done."

The Sunday letter made no mention of the premier's threats Friday to call an election, and dropped his demand that the schedules the opposition parties already removed be reinstated in the budget bill.

The legislature is scheduled to be recalled Wednesday for the final budget vote, and if it doesn't pass the minority government would automatically be defeated, launching another election.

The Liberals need only one NDP vote to pass the budget, or the New Democrats could abstain and allow the government to outvote the Conservatives, who have vowed to defeat the budget since the day it was introduced.

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  • What's In The Ontario Budget 2012

  • Health Care

    The 2012 Ontario budget freezes pay for doctors, and extends a pay freeze for health care executives. The province will begin means-testing seniors' prescription drugs, paid for under the Ontario Drug Benefit Plan, effectively meaning that the 5 per cent wealthiest seniors covered by the plan will have to pay more into the plan. Seniors with incomes over $100,000 and senior couples with combined incomes above $160,000 will be affected. Increases in health care spending will be capped at 2.1 per cent per year.

  • Education

    The budget freezes pay for teachers. A pay freeze for educational executives, already in place, will be extended. School boards in low-population areas will be amalgamated, and "under-utilized" schools will be shut. Student transportation will be cut by $34 million.

  • Senior Citizens

    The province will begin means-testing seniors' prescription drugs, paid for under the Ontario Drug Benefit Plan, effectively meaning that the 5 per cent wealthiest seniors covered by the plan will have to pay more into the plan. Seniors with incomes over $100,000 and senior couples with combined incomes above $160,000 will be affected.

  • Social Assistance

    Welfare rates will be frozen and planned increases to the Ontario Child Benefit will be delayed.

  • Taxes

    There are no tax hikes in the 2012 Ontario budget, but it does freeze the corporate tax rate at 11.5 per cent, foregoing planned reductions in the tax rate to 10 per cent. The freeze is expected to save $1.5 billion over three years.

  • Energy

    Ontario will cap the 10 per cent hydro bill rebate at 3,000 kilowatt-hours, a limit high enough that most homes won't be affected, but businesses could be. Reducing the tax credit will save $470 million over three years.

  • Crime & Security

    On top of the four jails the province already plans to close, the budget adds two more to the closure list -- one in Brantford and one in Chatham. Overtime for jail guards and the Ontario Provincial Police will be reduced.

  • Business Initiatives

    Ontario plans to reduce spending on business support programs by $250 million by merging a number of different programs.

  • Gambling & Lotteries

    The province aims to increase revenue by increasing the number of gambling facilities. [Details to come]