The measure has been described as the financial equivalent of nuclear weapons.
The closure of Russian banks from Swift will have a very large effect on the Russian economy, according to Nordea's chief economist Annika Winsth.
- It will affect Russian companies but also companies around the world that have had trade with Russia, she says in Ekonomibyrån.
In addition, the EU and the US are imposing sanctions on the Russian central bank's foreign exchange reserves, the world's fourth largest with assets of around $ 630 billion.
On Monday, the US Treasury Department also announced that it was banning transactions with the Russian central bank and the Russian state investment fund.
But the question is what effect economic warfare has on Putin.
Throttle deliveries
According to Torbjörn Becker, head of the Eastern Economics Institute at the School of Economics, Russia does not have much to oppose.
The Russian economy is relatively small compared to the sanctioning countries.
- The most significant threat from a purely financial point of view is that gas deliveries to Europe can be restricted, he says at the Swedish Financial Agency.
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