Is it permissible for a father to withhold financial support for his children if their mother prevents him from seeing them and participating in their upbringing, and if she has stripped him of his guardianship and authority over them by virtue of the positive law that grants custody to the mother until the age of 15?

The maintenance of children is obligatory upon the father by scholarly consensus, and it includes housing, food, drink, clothing, and education. It is estimated equitably according to the father's financial situation. The mother's custody does not negate the father's guardianship and his right to see and care for his children. He has the right to see his son while the son is in the mother's custody, and the mother is not permitted to prevent him from doing so. The jurists have stipulated that each of the parents of the child in custody has the right to see and visit them, and preventing this leads to the severance of kinship ties. Therefore, if the mother prevents the father from seeing his children, she is sinful for that, and the father has the right to bring her case before the Sharia judge. It is also advised to mediate and speak with the mother, and there is no objection to delaying maintenance to pressure her, while noting that maintenance is not forfeited by her disobedience.