I'm not sure what you're asking here exactly?

During (at least the early days) WWII, the UK wanted to suppourt France because everyone assumed that the French would be doing most of the fighting and France's eastern border would be where most of the fighting would take place. So the UK naturally wanted France to be a strong ally. I don't know exactly what you mean by proponent for power here though, it wasn't like Churchill or the UK was ever pushing France to be the new superpower or anything, they just wanted to support a strong ally who would be doing a lot of the allied fighting.

The question is harder to answer talking about later WWII, do you mean De Gaulle's government-in-exile? The Free French Forces and other partisans? The Vichy (who they were fighting)?

At least after WWII, Churchill was looking for another strong western european nation to counterbalance the rising Soviet Bloc, unfortunately De Gaulle ended up giving the finger to the UK and other wartime allies.