I am a british citizen married to a Nigerian and living in France. I am pregnant and intend to have my baby in France. Will my unborn baby's baby ( my grandchild) be a british citizen, or do I have to travel to the UK to achieve this?

LOL- let's your child has his/her own child and let them to decide.

Your grandchild will be a citizen of the country in which it is born.

Impossible to give a realistic answer as immigration laws will change significantly during the intervening years..

Thanks guys, for your valuable response.