McArthur River and Key Lake

Some 535 Cameco workers at the Saskatchewan company's McArthur River and Key Lake facilities could be affected by a strike or lockout. (Cameco)

Cameco is halting production at two of its Saskatchewan uranium operations over a labour-management dispute.

The Saskatoon-based company has initiated a shutdown at the McArthur River uranium mine as well as the Key Lake mill. 

The company says the union representing employees, United Steelworkers Local 8914, has given strike notice for Saturday night. 

In response, Cameco has issued lockout notice for that same time. 

It's shutting things down now to ensure safety, it says. Cameco says any labour disruption is not expected to affect its 2014 uranium delivery commitments to customers.

There are 535 unionized workers at the two operations.