Pope Pius XII delivers an Easter sermon in which he implores soldiers to let their conscience guide them.
From Pope Pius XII:
"To the powers occupying territories during the war, We say with all due consideration: let your conscience guide you in dealing justly, humanely and providently with the peoples of occupied territories. Do not impose upon them burdens which you in similar circumstances have felt or would feel to be unjust.
Prudent and helpful humanitarianism is the commendation and boast of wise generals; and the treatment of prisoners and civilians in occupied areas is the surest indication and proof of the civilization of individuals and nations.
But above all remember that upon the manner in which you deal with those whom the fortunes of war put in your hands may depend the blessing or curse of God upon your own land."
At no point does Pope Pius XII mention the plight of Jews being persecuted and killed by the Nazi regime. He doesn't even have anything specific to say about the persecution of the Catholic Church and Catholic priests in Poland.