The suspect was reportedly honked by ambassador Marek Magierowski’s car as he was walking in the middle of the road and, when Mr Magierowski emerged from the vehicle, the suspect spat on him.
The suspect said he was visiting the embassy for matters involving returning Jewish property in Poland, the newspaper added.
Emmanuel Nahshon, a spokesman for the Israeli foreign ministry, said an investigation was underway and that “we will update our Polish friends” on its progress.
“Israel expresses its full sympathy with the Polish ambassador and shock at the attack,” Mr Nahshon said.
“This is a top priority to us, as we are fully committed to diplomats’ safety and security.”
Relations between the two countries have become strained in recent years over a Polish law that criminalised blaming Poland for Nazi crimes during the Second World War, and an ongoing debate over the restitution of Jewish property seized during the Holocaust.