(Adds background, details from release)

July 26 (Reuters) – Miner Rio Tinto said on Monday it planned to cut production at its BC Works aluminium smelter in Kitimat, Canada to 35% following a strike initiated by the Canadian union Unifor after negotiation talks failed.

Unifor said on Sunday about 900 workers had started strike action at the miner's operations in the western Canadian province of British Columbia, after nearly seven weeks of unproductive talks over proposed changes to workers' retirement benefits and unresolved grievances.

Rio Tinto employs about 1,050 people at the BC Works smelter and Kemano powerhouse, of which the union represents about 900 workers.

The miner, which has been granted an essential services order by the British Columbia Labour Relations Board, said a reduced workforce is also in place to ensure the Kemano hydro-power facility continues to run. [https://refini.tv/2Wf54r0 ] (Reporting by Rithika Krishna in Bengaluru; Editing by Shinjini Ganguli)