Sayyiduna Ibn Umar (may Allah be pleased with them both) said: "I performed Hajj with the Prophet (peace and blessings be upon him), with Abu Bakr (may Allah be pleased with him), with Umar (may Allah be pleased with him), and with Uthman (may Allah be pleased with him), and none of them used to fast that day" — meaning the Day of Arafah.
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 13034