Sayyiduna al-Mustawrid (may Allah be pleased with him) narrates: Once I was with Sayyiduna Amr bin al-As (may Allah be pleased with him), and I said to him: I heard the Prophet (peace and blessings be upon him) say: "The harshest of people against you will be the Romans, and their destruction will only come with the Hour." Sayyiduna Amr (may Allah be pleased with him) said to him: "Did I not forbid you from saying things like this?"
Ahmad recorded it. Its chain contains a narrator, Ibn Lahi'ah, in whom there is weakness, and his narrations are hasan (good). The rest of its narrators are the narrators of the Sahih.