What is the ruling of Islamic law regarding a man who promised his wife that he would give her the price of an apartment to register it in her name in exchange for her staying with him abroad, then he needed this money, so he took it as a debt and promised to repay it, but he broke his promise and denied God's testimony to that?

A wife must obey her husband by moving with him to his place of residence. She is not permitted to refuse unless there is a legitimate Shar'i reason. If a husband grants money to his wife and she takes possession of it, it becomes her property, and he is not allowed to revoke his gift. If the wife lends money to her husband, he is obligated to repay it. If he is in straitened circumstances, he must be given time to repay. If he is affluent, he is not permitted to refuse repayment; otherwise, he would be a wrongdoer. If the wife willingly waives her right to the debt, it is a charitable act for which she will be rewarded.