The Crown corporation served a lockout notice last week and will be in a legal position to lock out the 50,000 unionized workers as of 12:01 a.m. Eastern Time on Monday.
CUPW says it declined the suggestion from Labour Minister MaryAnn Mihychuk for binding arbitration as a matter of principle and is hoping to reach a negotiated settlement.
Mihychuk added the federal government does have contingency plans in place in the event of a work stoppage.
The Canada Revenue Agency has deemed Old Age Security, Canada Pension Plan, Working Income Tax Benefit and the Canada Child Benefit cheques "essential" - even during a labour disruption.
Canada Post, like its global peers, is struggling to adjust to eroding mail volumes as customers turn to the Internet for communicating and paying bills. The union had rejected a request from the federal government to settle negotiations through arbitration earlier last week.
The ball is now in CUPW's court, but this makes it more likely there will not be a postal shutdown in the next few days.
"We are also expecting the union to honour their repeated public statements that they have no plans to issue a strike notice", Canada Post said in a news release issued Sunday.
Canada Post announced plans to gradually stop door-to-door delivery three years ago and replace it with community mailboxes, sparking opposition from citizens and politicians such as Montreal Mayor Denis Coderre.
Canada Post wants to change its pension scheme to bring it in line with the private sector.
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