TORONTO - Ontario's Liberal government is putting pressure on elementary school teachers to take part in a forum aimed at guiding collective bargaining.

Education Minister Laurel Broten accused the Elementary Teachers' Federation of Ontario on Monday of walking away from a discussion table that has proven productive in the past.

"We've repeatedly invited ETFO back, but they have repeatedly refused," Broten said. "They have chosen to withdraw and to be isolated outside the process."

With teacher contracts set to expire in August, the provincial discussion table allows teacher and staff unions and trustee associations to discuss issues, and come up with a framework for local collective bargaining.

The framework achieved at the last two discussion tables in 2005 and 2008 guided productive collective bargaining that included wage and other gains, Broten said.

Those gains, she said, could be in jeopardy now that the federation's delegation, led by president Sam Hammond, bolted after just one hour of a preliminary briefing.

"It's very unfortunate that the Elementary Teachers' Federation of Ontario has refused to participate," Broten said in calling on teachers and parents to press the union leadership to return to the forum.

The minority Liberal government, which is grappling with a deficit, has yet to pass a budget that, among other things, is counting on wage and grid freezes for teachers.

The federation said it was "studying the minister's request and consulting with legal counsel" and would issue a formal response this week.

Hammond has previously called the government's position insulting and mean-spirited.

Broten refused to say what might happen if the elementary teachers opt to bypass the ongoing talks at the provincial discussion table and go straight into local bargaining.

However, the Progressive Conservatives, who are pledging to vote against the budget, accused the minister of attempting to negotiate with teachers through the media.

The Tories want a mandatory wage freeze imposed on the broader public sector.

"The Liberal plan is to have a voluntary wage freeze and they pick and choose who they're going to ask to do this, which is just designed for failure," said Tory education critic Lisa MacLeod.

Economist Don Drummond recommended the province lift its cap on class sizes and eliminate full-day kindergarten, which will cost $1.5 billion a year, but Premier Dalton McGuinty has rejected those ideas and wants a wage freeze instead.

Broten said no one was under "any illusions" that the discussions would be easy, but said other education partners were at the table. It "simply isn't good enough" that the elementary federation walked away "without even trying," she added.