All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
If there is a sound Islamic evidence that a given month has started because its moon has appeared and has been witnessed by some people in a given country, then all the people in that country should act according to that evidence.
So, if Muslims in a country witness the moon and considering their sight of the moon the day of ‘Eed (tenth of Dhul Hijja) coincides with ‘Arafah day in Saudi Arabia, they should act according to their sight not that of Saudi Arabia or any other country.
No Muslim should act in contradiction with the Muslims of the country where he lives.
In fact, he must comply with the date the Muslim scholars in that country have fixed as the ‘Eed day as they base their judgement on sound evidence.
So, fasting and claiming that the day is the ninth while people in that place are celebrating the ‘Eed as the tenth is among the worst forms of mistrust that could cause relations between people to be greatly harmed. So, this practice is something that the Sharee’ah denies and closes all the doors that could lead to it.
We ask Allah to guide us and all other people to the right path.
Allah knows best.