Poland was invaded and conquered by Nazi Germany in the Fall of 1939. It was under Nazi occupation and control until the end of WWII.
Poland had no means by which to help the Jews of Warsaw.
Not only was Poland conquered and occupied, the Germans had enacted a brutal program designed to decapitate Polish leadership at all levels by killing anyone who could serve as a nucleus for resistance. Politicians, military, local officials, clergy and so on. There were few left to lead by the time of the Warsaw ghetto deportations.