The Harold Wilson government considered building three nuclear carriers as far back as 1966 but abandoned the idea on the grounds of cost. A deciding factor was the additonal cost of providing three nuclear powered escort cruisers. They are certainly no cheaper to build now than they were back then so why the idea was eventually resurrected I can't imagine?
Also, while there are times when France and Britain's foreign interests coincide they are also times when they are directly opposed such as during the recent invasion of Iraq.

