Nubaih bin Wahb brother of Banu Abd Al Dar said ‘Umar bin Ubaid Allah sent someone to Aban bin Uthman bin Affan asking him (to participate in the marriage ceremony). Aban in those days was the chief of the pilgrims and both were in the sacred state (wearing ihram). I want to give the daughter of Shaibah bin Jubair to Talhah bin Umar in marriage. I wish that you may attend it. Aban refused and said I heard my father ‘Uthman bin Affan narrating a tradition from the Apostle of Allaah ﷺ as saying A pilgrim may not marry and give someone in marriage in the sacred state(while wearing ihram). (Using translation from Abū Dāʾūd 1841)   

قَالَ رَسُولُ اللهِ ﷺ «لَا يَنْكِحُ الْمُحْرِمُ وَلَا يَخْطُبُ وَلَا يُنْكِحُ»  

[Machine] The Prophet ﷺ forbade marrying someone who is prohibited, or being married to, or proposing to them.  

عَنِ النَّبِيَّ ﷺ «نَهَى أَنْ يَنْكِحَ الْمُحْرِمُ أَوْ يُنْكِحَ أَوْ يَخْطُبَ»  

[Machine] The Prophet (Peace be upon him) said, "The prohibited person should not marry, nor propose."  

أَنَّ النَّبِيَّ ﷺ قَالَ «لَا يَنْكِحُ الْمُحْرِمُ وَلَا يَخْطُبُ»