I'm not asking to have my cake and eat it, no. All I want is a cake that's worth its weight

Emmanuel Macron

They would be deployed from January 1 to police the UK's "exclusive economic zone" (EEZ), which stretches up to 200 nautical miles from the coastline. The boats, which carry machine guns, would have the power to halt, inspect and impound any EU fishing boats illegally entering the area.

The preparations reflect the fact that ministers are concerned about the potential for struggles between rival fishing fleets if EU boats are suddenly banned from entering Britain's waters.