What is the ruling on divorcing a disbelieving wife who prevents her husband from worshipping, and leaving the children in her custody in a country that does not grant the husband the right of custody?

When a couple separates, the custody of young children goes to their mother unless there is an impediment. The disbelief or apostasy of the woman is an impediment to custody, so she has no right to custody of the children. Rather, the children follow their Muslim father in religion. The father must strive to bring his children to him to teach them Islam. If he exerts his effort and is unable, then there is no blame upon him.