Home2021 Treaties and Agreements ...Greece (21-610.1) – Protocol Amending the Agreement of April 22, 1980 hide Greece (21-610.1) – Protocol Amending the Agreement of April 22, 1980 TIAS Office of Treaty Affairs June 10, 2021 Foreign Assistance: Economic, Educational and Cultural Cooperation Signed at Thessaloniki September 28, 2020; entered into force June 10, 2021. Amendment of agreement signed April 22, 1980: TIAS 9754. Download Agreement [348 KB] Tags Cultural Exchanges Economic Affairs Education Foreign Assistance Greece Scientific and Technological Cooperation Treaties