Nafi' (may Allah have mercy on him) said that Abdullah bin Abdullah and Salim bin Abdullah both spoke to Abdullah bin Umar (may Allah be pleased with him) during the nights when al-Hajjaj descended upon Ibn al-Zubayr. They both said: It will not harm you if you do not perform Hajj this year, for we fear that something may be put between you and the House. Ibn Umar (may Allah be pleased with him) said: "We set out with the Prophet (peace and blessings be upon him) for Umrah, and the disbelievers of Quraysh blocked (the way to) the House, so the Messenger of Allah (peace and blessings be upon him) slaughtered his sacrifice and shaved his head, then returned."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 10079