Canada's national postal service has temporarily suspended operations, bringing the nation's mail delivery to a near complete halt on Wednesday.

The lockout of its workers by Canada Post comes after twelve days of rotating 24-hour strikes in Toronto and Montreal by the nearly 50,000 members of the Canadian Union of Postal Workers. The postal service says the strikes have so far caused over $100 million in losses. The work stoppages had already reduced mail delivery to three days a week in some urban areas.

The government-owned corporation says it needs to reduce employee benefits due to a $3.3 billion pension deficit – a figure disputed by the union. While the postal service has offered raises to existing employees, it says a lower hourly rate for new workers is necessary because of decreased revenue.

Negotiations are expected to continue on Wednesday, although the postal service says the two sides are “far apart” from reaching a deal.