Sunan Ibn Majah, Chapter: The Chapters on Tribulations

"Jubair said to me: 'Let's go to Dhu Mikhmar, who was a man from among the Companions of the Prophet (saw).' So I went with them and he asked him about the peace treaty (with the Romans). He said: 'I heard the Prophet (saw) say: "The Romans will enter into a peace treaty with you, then you and they will fight one another as enemies, and you will be victorious; you will collect the spoils of war and be safe. Then you will come back until you stop in a meadow with many hillocks. A man from among the people of the Cross will raise the Cross and will say: 'The Cross has prevailed.' Then a man among the Muslims will become angry and will go and break the Cross. Then the Romans will prove treacherous (breaking the treaty) (and will gather) for the fierce battle." Hadith 4089b. Another chain with a similar report to which he added: "They will gather for the fierce battle, and at that time they will come with eighty banners, under each of which will be twelve thousand troops."