Canada Post will neither confirm nor deny it will participate in a joint issue with the U.S. in 2006, as part of Washington 2006, as reported in Linn's Stamp News.
"The 2006 program is very much a program in the works at this point and we'll be announcing it probably at this time next year. We'll have to wait and see," spokeswoman Cindy Daoust told The Virtual Stamp Club.
Linn's reported that the stamps will commemorate a significant anniversary in 2006 of "a historical tie between the two countries."
Based on VSC's research, one guess might be the inauguration of the first transatlantic telephone cable, TAT-1, on September 25, 1956.
It was a joint venture of the U.S. and Canada, and linked North America (Newfoundland) with Great Britain (Scotland). Calls before then were carried by radio, and were very expensive.
The joint venture was funded by the Post Office Engineering Department, the Long Lines Department of American Telegraph and Telephone Company, Bell Telephone Laboratories and the Canadian Overseas Telecommunications Corporation.
There's a Web page (referenced on a Canadian Broadcasting Corp. page!) featuring stamps for Atlantic cables and submarine telegraphy:
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