Ikrimah bin Khalid states: I asked Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) about a woman whom a man wishes to marry while he is outside Makkah and also intends to perform Umrah or Hajj. Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) said: "Do not marry her while you are in the state of ihram, for the Prophet (peace and blessings be upon him) forbade it."
Ahmad recorded it; its chain contains Ayyub bin Utbah, who is da'if (weak), though he has also been declared trustworthy.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب النكاح / 7411