Au Contraire

The B model was deployed only in the UK, first with the V-force and later with the Tornado squadrons. NATO found the 450KT yield too high for a tactical nuclear weapon, that is why the C has ‘only’ 250KT…

The C Type was 190 kt not 250. This extract from the National Archives finally laid to rest that particular bit of the urban myths surrounding it.http://nuclear-weapons.info/images/tna-defe-11-470-e18-p3.jpg

The C type was below 200 kt at 190 kt because NATO policy decreed a 200 kt upper limit for tactical weapons in Continental Europe.

The use of the 450 kt Type B weapons was not confined to the UK either because they could be deployed elsewhere. Cyprus is one such place when the MEAF Canberras were replaced by Vulcans supporting the UK commitment to CENTO. See here http://nuclear-weapons.info/images/RAF-nuclear-frontline-Order-of-Battle-1966-94.PNG There’s also stuff in the archives at Kew that says they were deployed by VC.10 to Singapore by a westabout route for use by temporary detachments of Vulcans. Too laborious to dig it out just now and put on line. Trust me, it’s true.

Seems incongruous now, but in those times Iraq and Iran fellow CENTO members were still friends with us, and we regularly overflew their turf with nuclear weapons positioning to FEAF

For those wishing to look at the original archived source the ref is
DEFE 11/470 E18 p3.