Canada's Arctic sovereignty is not under increased threat despite recent forthright statements from the United States and the European Union spelling out their interests in the region, says Foreign Affairs Minister Lawrence Cannon.  But at least one northern leader is urging Ottawa to move faster to develop the North before Canadian goals are swamped by growing international interest in its resources and shipping routes.  "Here in Canada, we better pay attention and step up," Northwest Territories Premier Floyd Roland said Tuesday before heading off to a first ministers meeting in Ottawa later this week.    *, by Mike Blanchfield and Randy Boswell