Child born overseas entitlement to British Citizenship

I am looking to understand whether my newborn is already classed as a British citizen or not.

I am British (father),the mother is Filipino and the child was born in the Philippines. Myself and the mother are not yet married.

The complexity lies around the mother's relationship status at the time of the baby's birth. She was previously married to a Korean national and the divorce was recognised in Korea about 8 years ago. The divorce is yet to be recognised in the Philippines, however, as we are currently going through this long process.

Would the divorce papers from Korea therefore be sufficient and my child be able to apply for a first British passport? I note that one of the documents required for this is the mother and father's marriage certificate, what would we provide in place of this? If we would require the mother's certificate of no marriage from the Philippines then this is something that we don't have yet.

If the mother is still classed as married to another person because of her status in the Philippines and the fact she is Filipino, I understand we would have to register our baby as a British citizen first using form UKF(M). I am listed on the baby's birth certificate but I'd also like to understand whether a DNA test report would be required as proof of paternity?

Finally, once the baby has a Filipino passport I was hoping to bring mother and baby over to the UK on a general visitor visa for maximum 6 months stay to then sort out the citizenship and passport application from the UK as I believe it will be easier, especially if the likes of DNA tests are required. Would there be any issues with this?

Appreciate any advice that can be offered. Thanks in advance

Assume that child’s biological father was British otherwise than by descent at the time of child’s birth?

If the child’s mother was married to a non-British citizen at the time of birth, then registration may be under Section 3(1), probably using form MN1. The good news is that registration should be free, although some caseworkers may need to be lead to the right Guidance.

The Immigration and Nationality (Fees) (Amendment) (No. 2) Regulations 2020 specify that the fee can be waived in these cases. A fee will not therefore be needed for an application where the child would have become a British citizen, but for the fact that the mother was married to someone other than the child’s biological father at the time of the birth. If, however, on considering the case you find that the child does not fit into this category, but there are nevertheless grounds to register under section 3(1), you must request the fee.

Else, if child’s mother was not married at the time of child’s birth, then child is automatically British.