The Shanghai Cooperation Organization (SCO), led by China and Russia, is set to admit Belarus, a strong Russian ally, at its summit in Astana, Kazakhstan. This move aims to transform the SCO from a regional security bloc into a geopolitical counterweight to Western institutions. Belarus, which supported Russia’s 2022 invasion of Ukraine, joins after Iran’s admission last year. Founded in 2001, the SCO now includes 10 members, representing over 40% of the global population and a quarter of the world economy. The expansion follows the BRICS group’s recent membership growth.