It was narrated from 'Abdullah bin 'Umar that: a man asked the Messenger of Allah (ﷺ) "What clothes can the Muhrim wear?" The Messenger of Allah (ﷺ) said: "They should not wear shirts nor 'Imamahs, or pants, or burnoues, or Khuffs - unless a person cannot find sandals, in which cause he may wear Khuffs. But he should cut them to come lower than the ankles. And they should not wear anything that has been touched by (dyed with) saffron or Wars."
Source: sunnah.com
Other translations
Arabic
أَخْبَرَنَا قُتَيْبَةُ، عَنْ مَالِكٍ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّ رَجُلاً، سَأَلَ رَسُولَ اللَّهِ صلى الله عليه وسلم مَا يَلْبَسُ الْمُحْرِمُ مِنَ الثِّيَابِ فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " لاَ تَلْبَسُوا الْقُمُصَ وَلاَ الْعَمَائِمَ وَلاَ السَّرَاوِيلاَتِ وَلاَ الْبَرَانِسَ وَلاَ الْخِفَافَ إِلاَّ أَحَدٌ لاَ يَجِدُ نَعْلَيْنِ فَلْيَلْبَسْ خُفَّيْنِ وَلْيَقْطَعْهُمَا أَسْفَلَ مِنَ الْكَعْبَيْنِ وَلاَ تَلْبَسُوا شَيْئًا مَسَّهُ الزَّعْفَرَانُ وَلاَ الْوَرْسُ " .
sunnah.com