The US is sanctioning Russia's largest bank as part of a new round of financial penalties aimed at punishing Moscow for its support of separatists in Ukraine.
The US is also expanding sanctions targeting Russia's energy and defence sectors. The penalties come hours after the European Union enacted its own sanctions on Russian banks, arms makers and the country's biggest oil company.
The penalties prohibit persons in the US from providing equity or debt financing of longer than 30 days to Sberbank of Russia.
The bank is Russia's largest financial institution and accounts for approximately one-quarter of Russian banking assets and one-third of its banking capital, according to the administration of President Barack Obama.
The West is moving forward on sanctions despite a fragile ceasefire between Ukraine and the pro-Russian separatists.
New European Union sanctions curbing access to western financial markets for some of Russia's largest firms target banks, arms manufacturers and oil.
The country's leading oil company, Rosneft, is affected as well as the crude subsidiary of its state-owned energy giant Gazprom.
The measures published in the 28-nation bloc's official journal came as a beefed-up response to what the West sees as Russia's destabilising actions in Ukraine.
The sanctions also ban another 24 officials from travelling to the EU and freeze their assets there. Among the individuals are four deputy parliament speakers and leaders of the separatists in eastern Ukraine.
They also hit businessman Sergey Viktorovich Chemezov, who served in the Soviet intelligence service in Germany alongside President Vladimir Putin during the Cold War and is now known as one of his "close associates", according to the EU.
The sanctions curbing access to Europe's financial market also hit pipeline operator Transneft, arms firms and Russia's plane maker United Aircraft Corporation.
They forbid EU companies from engaging in new contracts in oil drilling, exploration and related services in Russia's Arctic, deep sea and shale oil projects. Russia's directly targeted oil major Rosneft is majority-owned by the state, but Britain's BP holds a 19.75% stake in it.
Conspicuously absent from the high-level targets chosen, however, were Russian gas companies - such as Gazprom - because Europe depends on Russian gas imports.
The new EU capital market sanctions ban credits and loans with a maturity of over 30 days for the targeted Russian banks and firms. Previous sanctions covered only debt and equity with a maturity of more than 90 days.
Limiting access to western capital markets curbs lending and is poised to weigh down Russia's already-flagging economic growth.
The export of high-tech items that can be used for both military and civilian purposes - so-called dual-use goods - is also facing further restrictions.