FJJP: UK's seat on UN Security Council, like France's, USSR's and (Nationalist) China's pre-dates its nuclear status, and derives from the Allies' victory,1945.
ABorges: UK's nuclear weapons competence is wholly derived from licences of US products. Chevaline, TK-100 penetration-aids enhancement of US W68 warhead, was done with no link to France, which persists in wholly-solo nuclear work.