bilateral
adjective
uk/baɪˈlætərəl/ usinvolving or affecting two different organizations, countries, etc.:
Futures contracts are bilateral agreements, with both the purchaser and the seller equally obligated to complete the transaction.
Mexico already has bilateral trade agreements with Colombia, Venezuela, and Costa Rica.
bilaterally
adverb uk/ˌbaɪˈlætərəli/ us/-ˈlæṱɚ-/
There are a number of matters that can be discussed bilaterally at the highest level.