THS
Err, that commodity is necessary for ALL ops (land, sea, air) and if you look at what they've bought it's all non-developmental. The alternative led to a lot of cost escalation with CdeG.
Yes necessary for ALL ops but not all fuels are created equal, nor do they cost the same.
F-76 is the most expensive 'standard' fuel the British military use* by a fair margin and the price of diesel derivatives will rise considerably again in the future as nations such as China and India once again develop a thirst for them.
F-35 on the other, whilst also experiencing price rises, is still considered a comparatively cheap fuel and you can run diesel vehicles on it, though not marine craft unfortunately.
It seems a little strange that we as a nation can be planning a new generation of nuclear powered submarines yet somehow fitting a nuclear power plant to the carriers is a huge leap in costs. Couldn't the costs somehow, I don't know, be shared between the projects?
* My information was correct as of October 07.