Musnad Ahmad 27:1499

Abdullah ibn Ahmad said: I found this hadith in my father’s book in his own handwriting: Aswad ibn Amir narrated to us, Ayyub ibn Utbah narrated to us, Ikrimah ibn Khalid narrated to us, who said: I asked Abdullah ibn Umar about a woman whom a man wanted to marry while he was departing from Makkah, intending to perform Umrah or Hajj. He said: "Do not marry her while you are in a state of Ihram, for the Messenger of Allah (peace and blessings of Allah be upon him) forbade that."