I attended the Eid with Umar bin Khattab, and he began with the prayer before the sermon. He said, "The Messenger of Allah ﷺ forbade fasting on these two days, the day of Fitr and the day of Adha. As for the day of Fitr, it is the day you break your fast, and on the day of Adha you eat from the meat of your sacrifices."
حدثنا سهل بن أبي سهل حدثنا سفيان عن الزهري
شهدت العيد مع عمر بن الخطاب فبدأ بالصلاة قبل الخطبة فقال إن رسول الله ﷺ نهى عن صيام هذين اليومين يوم الفطر ويوم الأضحى أما يوم الفطر فيوم فطركم من صيامكم ويوم الأضحى تأكلون فيه من لحم نسككم
Bukhari related it, in the Book of Fasting, the chapter on fasting on the day of Eid al-Fitr, hadith no. 5571 and 1990, and Muslim, in the Book of Fasting, the previous chapter, hadith no. 1137 (see the previous hadith, narrated from Zuhri, with the same wording).