Brazilian mining giant Vale has reached a tentative agreement with the United Steelworkers to end an Ontario strike that has lasted nearly a year.

The metals miner, formerly known as Vale Inco Ltd., said Sunday it settled on a new five-year contract with two union locals representing 3,000 nickel production and maintenance employees in Sudbury and Port Colborne.

Comprehensive memorandums of agreement are to be signed Monday.

"It's been a long strike and I think that both sides worked hard," said Cory McPhee, vice-president of corporate affairs. "Both sides wanted a deal and that ultimately was the driving force to this outcome."

The announcement comes just days after Ontario Labour Minister Peter Fonseca said the two sides had agreed to resume bargaining.

Firings caused impasse

Before reaching an impasse, the two sides had agreed on all issues except one — the firing of nine workers during the strike and whether they were entitled to arbitration.

A statement from Fonseca had said the impasse was not acceptable to the communities involved, nor the government.

A statement from USW Local 6500 said an agreement had been reached to have the firing issue heard by the Ontario Labour Relations Board, beginning Friday.

"This removes the remaining obstacle in the long struggle with Vale," the local said.

The union said ratification votes have been scheduled for Wednesday and Thursday in Sudbury and Thursday in Port Colborne.

The tentative deal contains a return-to-work protocol, but Vale says it is still unclear when the employees will be back on the job.

"Once the vote process is sorted out, we'll begin bringing people back to work," McPhee said. "Suffice to say, we're very happy to have a deal done."

Key issues included a bonus, job transfers, contracting out and pensions.

Vale's nickel business employs more than 11,000 people worldwide and had sales of $3.26 billion US last year, accounting for 13.6 per cent of the company's overall revenue. The company, which bought Inco Ltd. in 2006, changed its name from Vale Inco in late May.

The workers have been on strike since July 13, 2009. Vale said the settlements were reached with the help of mediators Kevin Burkett and Reg Pearson.

Fonseca, who also thanked the mediators, said in a release that he was pleased both sides were able to reach a deal.

"This is positive news for the families and communities affected by this long strike," he said.

During the strike, the union accused Vale of bad-faith bargaining and the company accused the union of "unlawful thuggery" over a variety of incidents on the picket lines.