Now, I don’t know you, I don’t know him and everyone is different.
When he says it to you first, it will come across as him declaring something to you.
When you say it to him, it will most likely come across as you forcing it on him.
Reason being, if you think in terms of having the power in the relationship, you’re going to be making “power plays” and doing all sorts of screwy and weird stuff to try and protect yourself from losing this imagined power. As a result, the guy will be weirded out and he’ll distance himself and put up emotional and mental barriers to protect himself from manipulation.
With these walls up, he’ll be harder to reach and you’ll end up trying harder and harder to break through to him.
And even if a guy does love you, he will feel to an extent that he’s being pressured.