This story is an ‘alleged’ transcript of an actual radio conversation between a US naval ship and Canadian maritime contact off the coast of Newfoundland in October 1995.
Unfortunately this tale is not true, but it is nevertheless a great story:

Americans: Please divert your course 15 degrees North to avoid a collision.

Canadians: Recommend you divert YOUR course 15 degrees South to avoid collision.

Americans: This is the captain of a US navy ship; I say again divert your course.

Canadians: No. I say again, you divert YOUR course.

Americans: THIS IS THE AIRCRAFT CARRIER USS LINCOLN, THE SECOND LARGEST SHIP IN THE UNITED STATES’ ATLANTIC FLEET. WE ARE ACCOMPANIED BY THREE DESTROYERS, THREE CRUISERS AND NUMEROUS SUPPORT VESSELS. I DEMAND THAT YOU CHANGE YOUR COURSE 15 DEGREES NORTH, THAT’S ONE FIVE DEGREES NORTH, OR COUNTER-MEASURES WILL BE UNDERTAKEN TO ENSURE THE SAFETY OF THIS SHIP.

Canadians: We are a lighthouse; your call