His remarks at a press conference in Berlin alongside German Chancellor Olaf Scholz sparked outrage in Germany, Israel and other countries.
At a press conference on Tuesday, Abbas refused to condemn Palestinian militants' deadly attacks on Israeli athletes at the 1972 Munich Olympics. Instead, he countered by saying he could point to the "50 Holocausts" by Israel. After receiving the complaint, it confirmed reports that Mr Abbas was being investigated for possible incitement to hatred. Starting does not automatically perform a full investigation.
Germany's foreign ministry said Abbas would be immune from prosecution because he was visiting the country on official business as a representative of the Palestinian authorities.
Germany does not recognize the Palestinian Territory as a sovereign state, Scholz reaffirmed on Tuesday.
Scholz said at a press conference on Wednesday that he was "disgusted with the outrageous remarks."
He added in his Twitter statement: We condemn any attempt to deny the crimes of the Holocaust.
Germany has long used the term "Holocaust" to describe the Nazis' singular crime of killing six million Jews before and during World War II.
On Wednesday, Abbas appeared to retract his comments. In a written statement, his office said, "President Mahmoud Abbas reaffirms that the Holocaust is the most heinous crime in modern human history."
The statement emphasized that "his response was not intended to deny the specificity of the Holocaust that occurred in the last century and to condemn it in the strongest terms."
