savezni

1. (of a state) federal
   Nemačka ima šesnaest saveznih pokrajina. — Germany has sixteen federal states.
   O tome odlučuje savezna vlada. — The federal government decides on that.
2. (of a sports association) of an association; national
   Savezni selektor je objavio spisak igrača. — The national team coach announced the squad.

For "allied" (troops, countries) Serbian usually uses "saveznički".