Canadian National (CN) conductors, train persons and yard persons have given strike notice ahead of a Tuesday deadline.

The union, which represents 3,200 workers, provided the 72-hour notice Saturday as contract negotiations continue this weekend.

The Teamsters Canada Rail Conference warned in October it was prepared to launch job action after over six months of unsuccessful talks.

A strike could begin at 12:01 a.m. ET Tuesday now that the notice has been provided.

The workers, mostly in major urban centres across Canada, have been without a contract since July 23.

Rob Reilly, executive vice-president and chief operating officer of CN, said in a statement that the company will continue to negotiate “in good faith” over the coming days.

“If a settlement cannot be reached this weekend, we will once again encourage the union leadership to accept binding arbitration as an alternative to disrupting the Canadian economy,” he said.

The strike notice comes a day after Montreal-based CN confirmed job cuts, saying it was “adjusting its resources to demand.” CN wouldn’t say how many people will be affected.