A person intends to perform 'Umrah during Ramadan. And because of traveling a long distance to Makkah, he is planning to use the relaxation of postponing the fasting during travel. My question is, is it correct to postpone an obligation for doing a Mustahib act (Umrah in Ramadan)?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

During Ramadan, a person who is traveling for any reason may break the fast and make it up later. So the permission of breaking the fast is not granted to obligatory type of the travel only. Rather, any one who travels for permissible reasons could break the fast, whether it is for a non-obligatory 'Umrah or for permissible business, as Allaah says about fasting (what means): {So whoever among you is ill or on a journey [during fasting days]-then an equal number of days [are to be made up]} [Quran 2:184]

Hamza Ibn 'Amru Al-Aslami said: "O Messenger of Allaah! I find within me the strength to fast while traveling. Would there be any blame upon me if I were to do so?" The Prophet answered: "It is a concession from Allaah. Whoever takes it has done well and whoever likes to fast, there is no blame upon him." [Muslim]

However, Imaam Al-Bukhari reported the same Hadeeth with the following wording: "Shall I fast during travel?" (And he used to fast a lot). So the Prophet told him: "If you wish you can fast, and if you wish you can break the fast."

Imaam Muslim also reported that Abu Sa'eed and Jaabir said: "We traveled with the Prophet so some of us broke the fast and some of us fasted, and none criticized or blamed the other for what he did."

So a traveler has the choice either to fast, or to break the fast and make it up later, if fasting does not cause him any harm. As regards the traveler who is harmed by fasting during his travel, then it is more appropriate for him to break the fast as the Prophet said: "It is not an act of virtue to fast during travel." [Al-Bukhari and Muslim]

Allaah Knows best.