The Department of the Treasury on Wednesday announced strengthened sanctions against two of Russia’s largest financial institutions that were already subject to U.S. restrictions.

Sberbank and Alfa-Bank, Russia’s largest and fourth-largest financial institutions, respectively, had full blocking sanctions imposed against them, steps taken to “further restrict” Russian President Vladimir Putin’s invasion efforts in Ukraine, Treasury Secretary Janet Yellen remarked in a press release. The two banks each had prior prohibitions placed on them by the Treasury on Feb. 24, though neither was subject to full blocking sanctions.