The ruling on (pronouncing) the Intention during Hajj and Umrah

Question :

Is it permissible to pronounce the intentions for performing 'Umrah or Hajj or Tawaf and Sa'y at the Sacred House? When is it permissible to pronounce the intention?

Answer:

Pronouncing the intention has not been reported from the Prophet for the prayer (As-Salah), the purification (i.e., Wudhu' and Ghusl), the fasting or anything from his acts of worship. Even for Hajj and Umrah, the Prophet would not say when he wanted to perform them: "O Allâh, verily I intend such and such." That has not been confirmed from him nor did he order any of his Companions to do it. The most that has been reported concerning this matter is that Dhuba'ah bint Zubair complained to him that she wanted to perform Hajj, but she was sick. Therefore, the Prophet said to her:
"Perform Hajj and make a stipulation (by saying): My place of removing Ihram is wherever You stop me.' For verily, you will get from your Lord what you made as an exception."

Here the statement is with the tongue only because the intent to make Hajj has the status of a vow, and the vow is with the tongue. This is because if the person intends to make a vow in his heart, it is not a vow and it is not considered as a vow. Since the Hajj is like a vow in the obligation to fulfill it upon beginning it, the Prophet commanded her to stipulate a condition with her tongue and to say: "If something (or someone) prevents me, then my place of removing Ihram is wherever You stop me."

In reference to what has been confirmed by the Hadith reported from the Messenger of Allâh of him saying:
"Verily, Jibril came to me and said, 'Pray in this blessed valley and say: An 'Umrah in a Hajj' (or he said: 'An 'Umrah and a Hajj"

This does not mean that he pronounced the intentions verbally. Rather, this means that he mentioned his type of Hajj within his Talbiyyah. Other than this, the Prophet did not say the intentions verbally.

Source:
Ash-Shaykh Ibn 'Uthaimin
Fatawa Islamiyah, Vol. 4 Pages 113-114