どちらともいえない

expression

not sure; can't say which

Used when you cannot decide between two options or when you are uncertain about something. Often used as a standalone phrase.

• AとBのどちらがいいか、どちらとも言いえない。

  I can't say which is better, A or B.

• その話はなしが本ほん当とうかどうか、どちらとも言いえない。

  I'm not sure whether that story is true or not.