It was narrated from Ibn 'Abbas (رضي الله عنه) that the Messenger of Allah (ﷺ) said to his companions:

"Make it ‘Umrah. If I had known before what I know now, I would have told you to do it ('Umrah). And let those who do not have sacrificial animals with them exit ihram.” The Messenger of Allah (ﷺ) had a sacrificial animal with him. And the Messenger of Allah (ﷺ) said: "’Umrah has been incorporated into Hajj until the Day of Resurrection.” And he interlaced his fingers.