I think you should separate them, they can hurt each other considerably if they get into a proper fight.

Then you start rebonding them after the spay.

Hopefully more members will come to this thread and give you advice. My bunnies are not bonded but they have been in fights and one fight resulted in a pretty bad injury to an eye.

I think chances are good that they can be good friends after their spays, because they don’t totally hate each other (yet). If one hurts the other badly, chances of a good relationship are a lot less good. They have long memories.

It’s typical of intact bunnies to cuddle one minute, then be at each other’s throats the next. This can happen with desexed rabbits too of course, but since yours have been brought up together and are still young, it is likely they will be able to re-bond post-spay.

I agree with separating them until they’ve both had and recovered from the surgery. After that I think bonding sessions will probably go a lot smoother and if the aggressiveness keeps up the stressing via car ride and other methods too will help. I hope they can get back to being good pals again soon!