Premier Dalton McGuinty is urging Ontario teachers to agree to new contracts before the new school year begins, while warning that he'll do it for them if they refuse.

McGuinty said he's confident teachers will return in September because they know the cash-strapped government can't afford to give them more money.

"I am very, very confident that the overwhelming majority of teachers understand our financial circumstances," he said Tuesday while visiting a school in Sault Ste Marie.

"They know we are the same government, they know this premier remains absolutely committed to publically funded education — it's my single greatest priority. That hasn't changed. What has changed is our financial circumstances and we need to be responsible given those changes."

But McGuinty also repeated his warning that he'd recall the legislature this month to impose new contracts if teachers and school boards can't reach local agreements that freeze wages for two years.

Some teachers have already scheduled strike votes for next month after failing to negotiate new contracts.

The old contracts will automatically roll over Sept. 1, giving teachers raises that the province's can't afford because it's facing a $15-billion deficit this year, McGuinty said.

Legislation is "always a last resort" and the best option is to negotiate agreements together, he said.

"That's what we've been able to do during the days when the wind was at our back," he said.

"Today the wind is in our face right across the global economy, so we've got to lean into it and push forward."

The governing Liberals want school boards to model any deals on their agreement with English Catholic teachers. But the Conservatives say that would give 40 per cent of teachers a raise and that McGuinty should have legislated a wage freeze for all broader public sector workers months ago.

The province's agreement with the Ontario English Catholic Teachers Association — covering 43,000 teachers at 29 boards — allows 35-40 per cent of teachers to get pay hikes by moving up the salary grid that rewards experience and qualification upgrades.

That deal also mandates three unpaid days off in the second year — which the government says amounts to a 1.5-per-cent pay cut for two-thirds of teachers -- and stops teachers from banking up to 20 sick days a year and cashing them out on retirement.

But four other unions representing teachers and support workers in elementary, secondary and francophone schools say they won't accept the same deal.

The school boards complain the threat of legislation isn't going to help resolve complex issues, and point out the province was able to reach only one major contract after five months of negotiations.