Ukraine crisis: What sanctions could West still impose on Russia?

In response to Russia's invasion of Ukraine, the US, UK, EU and more than two dozen other nations retaliated with economic measures that have sent the Russian rouble tumbling, cut major Russian banks from the global financial system and hurt state-owned firms and oligarchs, including Mr Putin himself.

The US says its actions hit 80% of banking assets in Russia; and the EU 70%. The allies have also taken steps to limit Russia's access to key technology, such as microchips and lasers; and moved against cryptocurrencies.

Together, they represent the toughest sanctions Mr Putin's Russia has ever faced.

And analysts expect policymakers to continue tightening - for example, by adding more kinds of technology and new companies to blacklists. The most recent action by the US, on Wednesday, targeted oil refining equipment, among other steps.

"We are at a seven or eight out of 10 on the escalation ladder right now," said Emily Kilcrease, senior fellow and director of the Energy, Economics and Security Program at the Washington think tank, the Center for New American Security. "There is definitely still room to go with tightening."

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