How can one retract a promise made to God regarding maintaining the minimum level of kinship ties?

This covenant with Allah is like an oath. There is no impediment to atoning for the oath and increasing ties with your brother. This is better, based on the Prophet's (peace and blessings be upon him) saying: "If any of you takes an oath and then sees something better than it, let him atone for his oath and do that which is better."