The upcoming international return to beyond Earth orbit exploration and commercialization is being formalized under the Artemis Accords, signed October 13, 2020.
https://www.nasa.gov/specials/artemis-accords/index.html
https://www.nasa.gov/specials/artemis-accords/img/Artemis-Accords-signed-13Oct2020.pdf
Founding signatories;
Australia
Canada
Italy
Japan
Luxembourg
United Arab Emirates
United Kingdom
United States of America
https://www.nasa.gov/press-release/nasa-international-partners-advance-cooperation-with-first-signings-of-artemis-accords