says who?
US /ˈsɛz huː/
UK /ˈsɛz huː/

1.
kata siapa?, siapa bilang?
used to express doubt or disagreement with a statement, implying that the source of the information is questionable or lacks authority
:
•
You can't do that. Says who?
Kamu tidak bisa melakukan itu. Kata siapa?
•
They told me I'm not allowed to enter. Says who?
Mereka bilang saya tidak diizinkan masuk. Kata siapa?