The United Arab Republic was a sovereign state formed by the union of Egypt and Syria in 1958. The same year, the Mutawakkilite Kingdom of Yemen (North Yemen), which had already signed a defense pact with Egypt, joined with the new state in 1958 in a loose confederation called the United Arab States. However, unlike the member countries of the United Arab Republic, Yemen remained an independent sovereign state. It maintained its UN membership, and separate embassies, throughout the whole period of confederation.
Neither the union nor the confederation fulfilled their role as vehicles of pan-Arabism and nationalism, as they were dissolved in 1961.