Musnad Ahmad 739:2

Yazid ibn Harun narrated to us, he said: Zakariya informed us, from 'Amir, from al-Harith ibn Malik ibn al-Barsa', who said: I heard the Messenger of Allah, peace and blessings of Allah be upon him, say on the day of the conquest of Mecca: "This shall not be fought against after today, ever, until the Day of Resurrection."