Mr Cameron has no such oil lake to call his own, but his support would provide some political cover if Mr Obama decided to release oil from the SPR without backing from the International Energy Agency, the rich-world oil club and supposed custodian of the world's strategic reserves.

ECONOMIST: Oil reserves

It was even better when Mr Cameron appeared to respond in kind with a slight on Salt Lake City by saying "of course it is easier if you hold an Olympic Games in the middle of nowhere".

BBC: Mitt Romney's Olympic mishap

According to an entry in the Clan Cameron Archives, Loch Arkaig, west of the Great Glen, has a "lake-horse" that in the past was seen by a deer stalker and his children.

BBC: Monsters Inc: Scottish lochs and their creatures