From the Federal Government's perspective, gradually taking all the governing authority that should have belonged to the New Nagaril Federation Government into its own hands would play an undeniable role in annexing Nagaril in fact!
People would certainly feel unaccustomed at first, but humans had a very strange tendency: they looked to the rich as examples! Once the rich in Nagaril's Mid-East began living like Federal citizens, or even became like Federal citizens, everyone else would begin trying it as well.
Changing everything from the top down could take decades.
Then there was the Mid-West. They could find a reason to develop it, then use improving living conditions and the like as an excuse to act against the western regions. The whole of Nagaril would then be completely remade in the image of the Federation! By that time, whether the New Federal Government existed or whether anyone listened to it would no longer matter!
Because people would already be accustomed to living, working, paying taxes, consuming, and dying like Federal citizens! It was possible that the Federal Government would never publicly declare that it had established nominal rule over Nagaril, maintaining this de facto rule indefinitely.
But it was also possible that they would.
By the time that day came, even if the Federal Government truly did so, there would be no opposition from Nagaril, because everyone would have long since grown accustomed to it! Especially the next generation—they might even be taught from childhood to believe that they were "Federal citizens," rather than "New Federal citizens."
This was a long-term, all-encompassing, gentle invasion—so gentle that people would not notice it until the invasion had already begun, and they would even cheer for it! Naturally, the Federal Government would also do everything it could to firmly seize all the powers