Musnad Ahmad 31:229

Suwayd ibn ‘Amr al-Kalbi narrated to us, Aban narrated to us, Qatadah narrated to us, from ‘Abdullah ibn Abi ‘Utbah, from Abu Sa‘id, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "The House shall surely be performed Hajj to, and it shall surely be performed ‘Umrah to, after the emergence of Gog and Magog."