Sayyiduna Abu Umayyah (may Allah be pleased with him) said: I came back from a journey to the Prophet (peace and blessings be upon him). When he (peace and blessings be upon him) was about to eat, I turned to leave, and the Prophet (peace and blessings be upon him) said: "Will you not have the meal?" I said: I am fasting. He (peace and blessings be upon him) said: "Shall I not tell you about the traveller? Allah has relieved him of fasting and half of the prayer."
Hadith Referenceالمعجم الكبير للطبراني / مسند من يعرف بالكنى / 19109