Is it permissible for the husband to cut off his wife's allowance, claiming she receives an insufficient allowance from the state?

It is not permissible for a husband to cut off his wife's maintenance (nafaqa) on the pretext of her wealth or that the state provides for her. Maintenance is obligatory upon him even if she is wealthy, because the reason for the obligation of maintenance is his enablement of her enjoyment or her confinement to him by the marriage contract, and not her need for money.