Anas bin Malik (RA) narrated that the Messenger of Allah (ﷺ) said: "Whoever prays Fajr in congregation, then sits and remembering Allah until the sun has risen, then he prays two Rak'ah, then for him is the reward like that of a Hajj and Umrah." He said: "The Messenger of Allah (ﷺ) said: Complete, complete, complete (Hajj and Umrah)."

Reference: Hasan (Albani). Tirmidhi: 586