In a speech to the American Society of International Law, Michael Wilson suggested the Canada-U.S. border should now be known as the longest “secure” border in the world, rather than the longest “undefended” border.

Wilson said much has been done to tighten up border security since 9-11. The two countries share intelligence daily and work closely together on immigration matters, and Canadian and U.S. police forces have integrated border enforcement teams.

But Wilson cautioned against the adoption of measures that would stifle legitimate travel between the neighbours.

"It is absolutely essential that the proper balance be achieved between economic and security objectives, between legitimate and illegitimate travel, between our joint border as a gateway and a checkpoint," he told his audience.