Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrated: The Prophet (peace and blessings be upon him) said: "By Allah, I will surely fight Quraysh." Then he said: "In sha' Allah." Then he said: "By Allah, I will surely fight Quraysh." Then he said: "In sha' Allah." Then he said: "By Allah, I will surely fight Quraysh." Then he said: "In sha' Allah."
Imam al-Tabarani recorded it in al-Mu'jam al-Awsat, and its narrators are the narrators of the Sahih.
Imam Abu Ya'la recorded something similar.