Nafi reported,

Abdullah bin Umar set out during the time of civil strife intending to perform Umrah. He said, "If I am prevented from reaching the House, we will do as we did with the Messenger of Allah ﷺ."So he set out and entered the state of ihram for Umrah. He continued on his way, and when he reached the high ground of Bayda, he turned to his companions and said, "Their affair is one and the same. I call you to witness that I have made Hajj obligatory upon myself together with Umrah."He went on until he came to the House. He circled it seven times and walked between Safa and Marwa seven times, doing nothing more than that, and he considered this sufficient for him. He also offered a sacrificial animal.

Muslim 2989

Sahih

و حدثنا يحيى بن يحيى قال قرأت على مالك

عن نافع

أن عبد الله بن عمر رضي الله عنهما خرج في الفتنة معتمرا وقال إن صددت عن البيت صنعنا كما صنعنا مع رسول الله ﷺ فخرج فأهل بعمرة وسار حتى إذا ظهر على البيداء التفت إلى أصحابه فقال ما أمرهما إلا واحد أشهدكم أني قد أوجبت الحج مع العمرة فخرج حتى إذا جاء البيت طاف به سبعا وبين الصفا والمروة سبعا لم يزد عليه ورأى أنه مجزئ عنه وأهدى

مسلم 2989صحيح
Contents
Reference
Commentary
Ayat
Collection
Sahih Muslim
Book
Hajj
Chapter
Permissibility of exiting ihram due to obstruction and permissibility of qiran
Numbering
Darussalam 2989
Muslim 2989