The Pope won't accept my gifts

Apologies if this has been covered elsewhere (I've had a quick look but found nothing) or if I'm being really simple.

My problem is that over the course of several campaigns, I've found myself unable to present gifts to the Pope. If I offer him Map Information, he'll thank me but insist on paying for it. If I offer him cash (one-off payment or regular tribute), he'll tell me that he can't accept because I'm too generous. If I offer him territory, he says something on the lines of "How can I be sure you won't try to get it back?".

Am I doing something obviously wrong? I wondered if my reputation made a difference but it doesn't seem to matter if I'm considered reliable or unreliable. I've tried starting with small cash gifts or huge presents and he'll take neither. Where I'm at on the pope-o-meter makes no difference apparently.

Anyone else had the same problem? Any help gratefully received.:help:

Don't just offer it like a normal offer of trade rights or something. There's a little "gift box" icon on the lower left, opposite the normal "offer" button --- make sure you select that when you make a gift. That ensures the AI knows you're just offering a gift.

Do what tequila said, but be aware that sometimes he'll still refuse.

Lowering the amount often helps.