Maybe just sabotage some federal aspirations but also did a lot to enhance and enlarge the free market aspects. What did France meaningfully contribute so we have a baseline for comparison?
I’m not saying UK played absolutely no role in building these institutions, but they’ve always displayed some reluctancy for further integration. Just fyi, France and Germany have been compensating since the 70s the budget contribution UK refused to make.
Like the League of Nations? And every other (defunt) supranational institution all the way back to Napoleon?