Answered by Shaykh Amjad Rasheed
If the new moon was seen in one city and its people fasted the whole month and then celebrated the Eid, and then one of those people traveled to another city which was far [s. different regions- ikhtilaf al-matla`] because its people had not seen the new moon in the beginning of the month like his people had, and so they were still fasting, should he fast with them or not?
Answer:
السؤال : رُؤي الهلالُ ببلد فصام أهلُه وأتموا شهرهم فأصبحوا معيِّدين فسافر شخصٌ منهم وهو مُعَيِّدٌ إلى بلدٍ مختلفِ المطلع لم يروا الهلال مع بلده أول الشهر فوجدهم صياماً ، فهل يبقى مفطراً أو يجب عليه الإمساكُ ؟ الجواب : الأصح كما في “المنهاج” للإمام النووي : أنه يجب عليه الإمساكُ ؛ قال في “التحفة” (3/385) : لأنه صار مثلهم .
The most correct position, as is in the Minhaj of Imam al-Nawawi, is that it is obligatory on him to fast with them. He said in the Tuhfa, (3:385), “Because has become like them.”
Amjad Rasheed
[Translated by Sr. Shazia Ahmad]