It is narrated from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) said: "This is an ‘Umrah from which we have benefited, so whoever among you does not have a sacrificial animal with him should come out of the state of Ihram, for now ‘Umrah has been incorporated into Hajj until the Day of Resurrection."
Hadith Referenceمسند احمد / ومن مسند بني هاشم / 2115