What’s the correlation between the portuguese “né” and the japanese “ね”(ne)?

This might seem like a weird a question but the both of them are used in the exact same way (from my limited knowledge of japanese), both can be translated as “isn’t it?”. And are used at the end of sentences to ask for confirmation.

Is there some history that made this same word to be shared by languages so far apart?

by GabrielToppersson