reciprocal
adjective
formal uk/rɪˈsɪprəkəl/ usinvolving two people or organizations who agree to help each other by behaving in the same way or by giving each other similar advantages:
a reciprocal arrangement/agreement/relationship
We have agreed to exchange information about our two companies, but strictly on a reciprocal basis.
reciprocally
adverb
We aim to establish reciprocally profitable relations.