Definitely French because of the forged Simplex rear DO'S and the Vitus fork.
Pink paint on it might suggest it's a Mercier, but I would expect the Mercier crown cast into the fork shoulders if it was.....
Although the scalloped seat stay ends is a good sign, quality-wise, the Vitus 172 fork blades suggests a mid level model at most if the fork is original today the frame. A top level model would have had "Supervitus" fork blades. The very basic Weinmann 405 brakeset suggests the same.....