Nafi reported,

Ibn Umar intended to perform Hajj at the time when Hajjaj had laid siege to Ibn Zubayr. The narrator related the same story, and at the end of the hadith said that Ibn Umar used to say, "Whoever combines Hajj and Umra, a single tawaf suffices for him, and he does not exit the state of ihram until he has completed both together."

Muslim 2991

Sahih

و حدثناه ابن نمير حدثنا أبي حدثنا عبيد الله

عن نافع قال

أراد ابن عمر الحج حين نزل الحجاج بابن الزبير واقتص الحديث بمثل هذه القصة وقال في آخر الحديث وكان يقول من جمع بين الحج والعمرة كفاه طواف واحد ولم يحل حتى يحل منهما جميعا

مسلم 2991صحيح
Contents
Reference
Commentary
Ayat
Collection
Sahih Muslim
Book
Hajj
Chapter
Permissibility of exiting ihram due to obstruction and permissibility of qiran
Numbering
Darussalam 2991
Muslim 2991