Is it still required to provide a cookie warning offering users the ability to opt in/out of cookie tracking?

I cannot find any official advice on what we are supposed to be doing.

I'm not looking for answers along the lines of "to be on the safe side", but official guidelines. Does the cookie warning need to be on the homepage / every page / privacy policy page etc.

It seems most companies have implemented solutions based on best guesses, I can't see a consistent trend.