The 32-year-old player will be absent at the 2019 FIVB Volleyball Men's World Cup which will be held in Japan in October.
Mousavi has told Iran coach Igor Kolakovic he needs more time off since he is exhausted.
Mousavi will travel to Poland instead of accompanying the national team in the World Cup.
Indykpol AZS Olsztyn, based in Olsztyn, plays in the Polish Volleyball League (Polska Liga Siatkówki, PLS).
It is one of the most successful clubs in Poland.