Metal exchanges facilitate the trade of industrial metals around the globe. So as a result of Friday’s actions, metal exchanges, like the London Metal Exchange (LME) and Chicago Mercantile Exchange (CME), will be prohibited from accepting new aluminum, copper, and nickel produced by Russia. These actions are meant to further limit Russia’s revenues that help fund its war machine against Ukraine. 

Reducing Russia's Revenues from Metals - by Irene Kenyon (substack.com)