Chapter: It is permissible to fast or not to fast during Ramadan for one who is travelling for no sinful purpose, if his journey is two stages or further. But it is better for the one who is able to fast without suffering any harm to do so, and the one for whom it is difficult may break the fast
Humaid reported that Anas (Allah be pleased with him) was asked about fasting during Ramadan while travelling. He said: We travelled with the Messenger of Allah ( صلی اللہ علیہ وسلم ) during the month of Ramadan, but neither the observer of the fast found fault with the breaker of the fast, nor the breaker of the fast found fault with the observer of the fast.
Authentic