Ontario reached a tentative contract deal Friday with its largest teachers' union following a highly contentious round of bargaining.

The agreement with the Elementary Teachers' Federation of Ontario (EFTO) means the government has now secured tentative deals with two out of the four major unions.

No details were revealed, but Education Minister Stephen Lecce said in a statement that the government is committed to maintaining class sizes and full-day kindergarten, investing in special education and a "fair" increase in compensation.

"We remain focused on landing further deals, to provide stability and certainty to students, parents, and educators," he wrote.

The government has previously said it would not budge beyond an offer to increase wages and benefits by one per cent per year.

Major unions had asked for 2 per cent on salary

The major unions had asked for two per cent on salary and around six per cent on benefits.

ETFO said while its provincial executive endorses the deal, ratification will ultimately be up to its 83,000 members. The union didn't say when the votes would happen.

"This has been a very prolonged and difficult bargaining process," ETFO president Sam Hammond said in a statement.

"We are very grateful for the support and unwavering solidarity of our members and the public who have continued to stand up for public education and the supports that our students and educators need now and in the future."

The government had also been looking for concessions on a regulation that dictates seniority-based hiring.

Elementary teachers had been on a work-to-rule campaign since the fall and staged rotating strikes until shortly before schools were closed due to the COVID-19 pandemic.

The Ontario English Catholic Teachers' Association reached a tentative deal with the government earlier this month and is holding ratification votes April 7 and 8.

The Ontario Secondary School Teachers' Federation and the union representing teachers in the French-language system remain without deals, though the latter has been in regular bargaining.