Jabir bin Abdullah (may Allah be pleased with them both) said: I heard the Messenger of Allah (peace and blessings be upon him) say: "The place for the people of Iraq to begin the talbiyah is Dhat Irq."
This is how Abdullah bin Lahi'ah narrated it; the correct version is the narration of Ibn Jurayj, and it is possible that Jabir heard Umar bin al-Khattab (may Allah be pleased with him) say this about the miqat of the people of Iraq.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 8912