The President of the European Commission, Ursula von der Leyen, will propose to EU leaders to exclude certain Russian banks from international payment system SWIFT.

Her statement came Saturday evening at a press conference.

A variety of sanctions have already been adopted against Russia. Excluding the banks from SWIFT will further impact Russia's export options.

According to economist and chief analyst at Danske Bank Jens Nærvig Pedersen, however, it doesn't appear as if it will affect oil and gas trade, on which Russia and Europe are both heavily dependent.

A full exclusion of all Russian banks from SWIFT would mean that Europe would no longer be able to buy oil and gas in Russia.

"In theory, it's possible to transact while bypassing SWIFT, but it would be difficult in practice. If all the banks were excluded, it would likely be difficult to continue trading with oil and gas," says Nærvig Pedersen.

Nærvig Pedersen regards the fact that only certain banks would be encompassed as a sign that EU wants to crack down hard on the financial sector, but doesn't want to shut down the opportunity of buying gas and oil in Russia.

"In the way that the sanctions were presented on Saturday, it might look as if the energy trade is exempt based on the fact that they have been devised in this manner."

If Europe were no longer able to buy oil and gas in Russia, it would have huge consequences.

"It would affect consumers, and it would affect businesses. It's also important for the transport sector, so it would impact European economy broadly," says Nærvig Pedersen.

In the past year, a third of EU nations' natural gas and a fourth of their oil have been imported from Russia, according to figures by Eurostat, which compiles statistics on EU member nations.

A halt to Russian oil and gas imports would result in significant prices surges for gasoline and electricity, according to Nærvig Pedersen.

"If it is shut off overnight, it would most likely be considerably more expensive, at least to begin with," he says.

"We have seen crises in the Middle East where oil exports were affected, but Russia is one of the leading producers of oil and gas. It's a wholly different scale from what we have seen before."

It is not yet clear which banks stand to be excluded from SWIFT. According to Nærvig Pedersen, it is difficult to predict the exact consequences of the such a sanction.

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