Found some articles claiming this but also others disputing it. France does not appear to get much Uranium from Mali.[1] Although I would not put it past them having an interest in future Uranium prospects.

[1] "France uses some 12,400 tonnes of uranium oxide concentrate (10,500 tonnes of U) per year for its electricity generation. Much of this comes from Areva in Canada (4500 tU/yr) and Niger (3200 tU/yr) together with other imports, principally from Australia, Kazakhstan and Russia, mostly under long-term contracts. Areva perceives the front end of the French fuel cycle as strategic, and invests accordingly." https://www.world-nuclear.org/information-library/country-pr...