Musnad Ahmad 932:7

Zakariya narrated to us, Ubaydullah ibn Amr narrated to us, from Abdullah ibn Muhammad ibn Aqil, from al-Tufayl ibn Ubayy ibn Ka'b, from his father, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "When the Day of Resurrection comes, I will be the Imam (leader) of the prophets." He then mentioned its meaning.