On the basis of this groundwork, Mir as a system was formalized in 2014 as a way to overcome potential blocks of electronic payments, after several Russian banks were denied services by US-based Visa and MasterCard because of the sanctions regime against them.[5] The first cards working on the Mir system were launched in December 2015.[6] Sberbank, Russia's leading bank, started issuing them in October 2016.[7] By the end of 2016, 1.76 million Mir cards had been issued by 64 banks.[8] As of February 2021 89.4 million cards have been issued.[9] 3.5 billion payments were issued using Mir in 2020, 75% more than in 2019.[10] In March 2021, the payment system announced a ban on the replenishment of foreign electronic wallets.