Vale said it will bring in outside workers to increase production at its strike-bound nickel operations at Ontario’s Sudbury mines.

The move comes after the striking workers rejected a contract settlement offer from the company, prolonging a strike that began in July 2009.

The company already resumed copper mining at Sudbury last September and partially restarted its nickel smelter in January by using employees from other divisions.

Last month Vale announced it will resume nickel operations at its Coleman and Creighton mines in Sudbury using outside contractors.

Mined nickel will be smelted and shipped to the company’s Clydach Refinery in Wales, which expects to be at full capacity by April, producing 3,600t of nickel a month, according to Reuters.

Vale has also resumed production in Newfoundland and Labrador at the Voisey’s Bay nickel mine and processing plant.

The company said it is increasing production at Sudbury to ensure the continued supply of nickel ore to the smelter and expects to maintain full and continuous production by the end of the second quarter.

In 2009 output from Vale’s Sudbury mines fell sharply due to low demand and labour stoppages.