Is it permissible to eat and drink water from the plates or cups of polytheists and People of the Book?

It is regarded permissible to eat and drink water from the plates or cups of polytheists and People of the Book if it is not obvious that or if we do not know that there was something that Islam prohibited in those plates or cups. It is not permissible to eat from them if it is known that they were contaminated with najasah.

The Messenger of Allah drank water from the waterskin of a polytheist woman. He also ate food from the plates of the People of the Book.