Sayyiduna Ibn Abbas (may Allah be pleased with them both) narrates that the Prophet (peace and blessings be upon him) entered into Ihram with the intention of Hajj. Upon reaching Makkah, he performed Tawaf of the Ka'bah and Sa'i between Safa and Marwah, but due to having brought the sacrificial animal, he did not shave or cut his hair to become halal. And he instructed those who had not brought the sacrificial animal with them to "perform Tawaf and Sa'i, and after shortening or shaving their hair, they should become halal."