The Stillwater Mining Company has reached a tentative labour agreement with the Paper, Allied Industrial, Chemical and Energy Workers (PACE) International union.

Representatives for Stillwater explained that the current agreement would be extended until July 12 to allow the union's members time to review and ratify the new arrangements.

Stillwater mining company operates the Stillwater Mine and East Boulder Mine in Montana, USA.

It is the only US producer of palladium and platinum and is the largest primary producer of platinum group metals outside of South Africa.

Palladium accounts for about three-quarters of the pgm extracted, with the remainder largely platinum.