The so-called US law banning export of technologically sensitive weaponry has a special loophole. They'll sell anything to UK including nukes, and vice versa. From the 60s to 80s, US and UK forces used the same F4 Phantom (the premier warplane of that era), Sea Harrier (the pioneer STOL/VTOL warplane of that era), Poseidon (nuke) and Trident (nuke). These are the only two countries that trade nukes legally and open declared. Speaks volumes about that fabled special relationship.
However, UK isn't interested in F22 Raptor as its BAe is involved in Panavia and Eurofighter projects since joining EC/EU. That's why now UK has Tornadoes and Typhoons instead of F15/16/22s. All other countries can apply to by a modified export-eligible version, called F35 Lightning II. Japan wants the F22, not the F35. Negotiations are still underway for a less modified version that's more F22 than F35. Singapore settled for F15SG, which I think is good enough for the task and circumstance. Unlike Japan, Singapore's not preparing to fight Russia, is it?