Mr Cameron and his team have spent the last few days in Guam, docked at the port, re-supplying the ship that has been their home for the last few months.

BBC: James Cameron gets ready to dive to the Mariana Trench

For example, Britain's defence secretary during the Falklands war, John Nott, revealed in his memoirs that France had been Britain's staunchest ally, providing information that helped to render the Exocet anti-ship missiles used by Argentina ineffective, and supplying Mirage and Super-Etendard fighters for British Harrier pilots to pit themselves against in training.

ECONOMIST: The Anglo-French defence pact