Musnad Ahmad 492
It was narrated that Nubaih bin Wahb said:
Ibn Ma`mar wanted to marry his son to the daughter of Shaibah bin Jubair. So he sent me to Aban bin `Uthman who was the Ameer of Hajj. I came to him and said to him: Your brother wants to arrange his son`s marriage and wants you to witness it. He said: I think you are no more than an ill-mannered Iraqi. The pilgrim in ihram should not get married or arrange a marriage. Then he narrated a similar report from `Uthman (رضي الله عنه) and attributed it to the Prophet (ﷺ)
حَدَّثَنَا إِسْمَاعِيلُ، حَدَّثَنَا أَيُّوبُ، عَنْ نَافِعٍ، عَنْ نُبَيْهِ بْنِ وَهْبٍ، قَالَ أَرَادَ ابْنُ مَعْمَرٍ أَنْ يُنْكِحَ، ابْنَهُ ابْنَةَ شَيْبَةَ بْنِ جُبَيْرٍ فَبَعَثَنِي إِلَى أَبَانَ بْنِ عُثْمَانَ رَضِيَ اللَّهُ عَنْهُ وَهُوَ أَمِيرُ الْمَوْسِمِ فَأَتَيْتُهُ فَقُلْتُ لَهُ إِنَّ أَخَاكَ أَرَادَ أَنْ يُنْكِحَ ابْنَهُ فَأَرَادَ أَنْ يُشْهِدَكَ ذَاكَ فَقَالَ أَلَا أُرَاهُ عِرَاقِيًّا جَافِيًا إِنَّ الْمُحْرِمَ لَا يَنْكِحُ وَلَا يُنْكِحُ ثُمَّ حَدَّثَ عَنْ عُثْمَانَ رَضِيَ اللَّهُ عَنْهُ بِمِثْلِهِ يَرْفَعُهُ‏.‏