Is it permissible for a man to spend on his pregnant wife or on the one with children after divorce, if she expelled him from the house exploiting the British law that provides for her?

If the house is owned by the husband, the wife has no right to expel him from it. If it is owned by her, then she has the right to do so. A law that contradicts Sharia is not to be considered.

The husband is obliged to provide maintenance and lodging for his non-rebellious divorcee during her waiting period (iddah) of a revocable divorce. She has no maintenance or lodging after her iddah becomes irreversible unless she is pregnant.

The maintenance of children is obligatory upon the father as long as they are young and have no wealth. The maintenance of a pregnant woman is not waived by the wife's rebellion or injustice. The maintenance of children is obligatory upon the father, whether the wife is rebellious or not.

A woman in her waiting period (iddah) from a revocable divorce is treated like a wife. Therefore, she is not permitted to leave the marital home, nor is he permitted to expel her, as Allah Almighty says: "Do not expel them from their homes, nor should they leave, unless they commit a clear immorality."