From the US Postal Service:
Canada Post informed us today that their suspension of service will last at least until some time next week as they await the Canadian governmentâ€™s action on back-to-work legislation.
As a result, effective 11:59 p.m. CDT Saturday, June 18, USPSÂ® will stop accepting all mail destined for Canada, with the exception of Global Express Guaranteed (GXG) service.
Customers can avoid service disruptions by using GXG service, which is available online at www.usps.com and at thousands of participating retail locations throughout the U.S.
We will continue to closely monitor the situation. Once Canada Post announces that they will resume operations, we will again begin accepting mail destined to Canada and mail currently being held in our network will be dispatched.
Additional information and updates regarding acceptance and movement of international mail is available at http://www.usps.com/communications/news/serviceupdates.htm.