US payment card firms Visa Inc and Mastercard Inc have blocked multiple Russian financial institutions from their network, complying with government sanctions imposed over Moscow’s invasion of Ukraine.

Visa said on Monday it was taking prompt action to ensure compliance with applicable sanctions, adding that it will donate $2 million for humanitarian aid. Mastercard also promised to contribute $2 million.

“We will continue to work with regulators in the days ahead to abide fully by our compliance obligations as they evolve,” Mastercard said in a separate statement late on Monday.

The government sanctions require Visa to suspend access to its network for entities listed as Specially Designated Nationals, a source familiar with the matter told Reuters. The United States has added various Russian financial firms to the list, including the country’s central bank and second-largest lender VTB.

On Saturday, the US, Britain, Europe and Canada announced new sanctions on Russia – including blocking certain lenders’ access to the SWIFT international payment system.

Russians rushed to ATMs and waited in long queues on Sunday and Monday amid concerns that bank cards may cease to function, or that banks would limit cash withdrawals.

Russia calls its actions in Ukraine a “special operation”.

Many Western banks, airlines and more have cut ties with Russia, calling the country’s actions unacceptable. European nations and Canada have shut their airspace to Russian aircraft.

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