It was narrated that Ibn 'Umar said; "A man came to the Prophet and said: “What should we wear when we enter Ihram?' He said: “Do not wear a shirt, or an 'Imamah, or pants, or a burnouts, or Khuffs unless you cannot find any sandals. If you cannot find any sandals, then wear something that comes beneath the ankles””"
SahihSahihIsnaad SahihBook 24 · Hadith 58