The US Depository boss said the EU's restriction on seaborne Russian oil could make rough costs take off.

The typical Price of gas in the US has fallen consistently since hitting a high above $5 in June.

"It's a risk," she told CNN's "State of the Union" Sunday, having been asked whether gas prices could rise again in 2022.

"This winter, the European Union will cease, for the most part, buying Russian oil," she said. "And, in addition, they will ban the provision of services that enable Russia to ship oil by tanker. And it is possible that that could cause a spike in oil prices."

The EU is set to end all seaborne imports of Russian unrefined on December 5, satisfying a promise its individuals made while concurring a 6th authorizations bundle against Moscow in June.

Yellen anticipates that that ban should push up oil costs as worldwide stockpile fixes, which could thus push up costs for US gas.