Your scenario does not have enough information for valid advice. This is a negotiation, and you haven't mentioned what your leverage is, if any. If you have non

Your scenario does not have enough information for valid advice. This is a negotiation, and you haven't mentioned what your leverage is, if any. If you have none, you're at their mercy, and negotiation is impossible - you will have to do as they say. If you have some (such as being valuable to the company and a possible flight risk), then you can just put your cards on the table. A manager worth their salt will try to retain a hard-to-replace employee. This only works, however, if you're prepared to walk away, so I'd get another offer in advance.