This should have been discussed BEFORE you married him.
At this point, yes, it is unreasonable for him to put "conditions" down. You have a decision to make. Do you concede and make more of an effort to win his daughters affections, which is not really in your control, or do you consider an alternative, possibly including another relationship.
A marriage counselor might be of benefit.
I'm glad you did talk about this.
Still, you can't control his daughters affections towards you, no matter what you do. He's giving you a condition over which you have little/no control. Ask him about that.
Counseling may still be an option.
It is a topic that has to remain open for discussion. However, sit down and plan and if necessary involve a 3rd party that won't be bias towards either of you.
Having a child is a BIG deal, so many females think that "it's my body, so it's my baby and I will decide" - This is so UNTRUE, a baby born by 2 people who are ready and want a child has a better chance being born into a loving and rationale home. LOVE alone won't help you raise your child and there are so many children with ONE parent, why keep repeating history. It appears that you husband sees something in you and feels within himself that an additional human is not what you both need.
Are you financial set - kids costs nearly 1/2 million dollars or more today. Are you and your husband on set career paths or jobs that you can see doing and having for the next 30 years? More importantly, are you able to stay home with your children for the first 2-4 years of his or her life. I have found that children need constant care up until their teens years - one parent who is home or at least part-time - you just get a better person unless you have a large family that can assist and raise your children as you want and there are no fractures in child rearing.
Why not further your education and make sure you are grounded - what is the rush - and anyone who says there should be NO CONDITIONS is lying - each and every relationship has to have standards and conditions - it's part of being human and not animals - and even animals have conditions.