Elementary teachers in Ontario are stepping up their job action today with a new phase of their work-to-rule campaign.

Teachers won't be supervising extra-curricular activities outside regular school hours, participating in field trips, or participating in assemblies, except to supervise students.

They are also threatening to start rotating strikes next Monday "if the government refuses to address critical issues" by Friday.

Sam Hammond, president of the Elementary Teachers' Federation of Ontario, said that ongoing contract negotiations with the province have entirely stalled.

"We spent four months at the table from late August until Dec.19 with absolutely no engagement, meaningful negotiations on behalf of the government," he told CBC Radio's Metro Morning.

"We honestly feel like we have no other option but to do what we're doing."

Hammond said he understands that rotating strikes will be difficult for parents and students alike.

"But I say to parents, we need them. We need them to stand with us to protect the future of publicly-funded education in this province."

Sam Hammond, President of the Elementary Teachers' Federation of Ontario, explains how their work-to-rule job action, starting today, will affect students. 8:31

This round of contract talks has been difficult between the government and all major teachers' unions, with most at varying stages of job action.

In English Catholic schools, teachers will start their own work-to-rule campaign, including not participating in standardized testing, preparing report card comments or participating in Ministry of Education initiatives.

And on Wednesday, high school teachers will stage the latest in a series of rotating strikes, this one affecting boards in Ottawa, Hamilton, Durham Region and other areas across the province.

Education Minister Stephen Lecce says teachers in the French system have also announced a work-to-rule campaign, but the union would only say that it will talk about the next steps in the bargaining process at a press conference on Tuesday.

Compensation is sticking point, Lecce says

Catholic and high school teachers were angered when the Tories announced in March that average secondary school class sizes would jump from 22 to 28 and four e-learning courses would be mandatory for graduation.

The province has since scaled back those increases, to an average class size of 25 and two e-learning courses, but the unions say that's not good enough.

All of the major teachers' unions are also going to court to challenge legislation that caps wage increases for public sector workers.

For elementary teachers, the union has said key issues are more supports for students with special needs, addressing violence in schools and preserving full-day kindergarten.

Speaking to reporters at Queen's Park on Monday afternoon, Lecce urged teachers' unions not to escalate their job actions.

"I think further escalations by teachers' unions are adversely impacting students in this province," he said.

"We think the pathway forward is to work constructively with the government to get a deal; to make the case for the teachers' unions at the bargaining table and not to withdraw services from our kids, not to walk out on them, not to undermine their learning potential."

Lecce has repeatedly said the key sticking point in negotiations with high school teachers is compensation, with the union demanding a roughly two-per-cent wage increase and the government offering one per cent.