European Commission Vice-President for Values and Transparency Vera Jourova said, on Sunday, that several European countries would face a major energy crisis if Russian energy imports were completely prohibited.

"We are working on the sixth package of sanctions [against Russia] at the moment. However, we must check the willingness of the member countries to uphold these measures before imposing any sanctions. The starting point is not an easy one, especially with regard to gas. A full gas embargo could result in a major energy crisis in a number of countries," Jourova added as quoted by Swiss newspaper Neue Zuercher Zeitung.

Furthermore, Jourova went on to say that Europe must reduce its reliance on Russian energy sources and halt oil and gas imports "as soon as possible."

"It is regrettable that we have become so reliant on Russia in the past," the Vice-President said, adding that "more could have been done" to put pressure on Russia.

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The European Commission previously stated that Moscow would be the EU's primary supplier of energy sources in 2021, with Russia accounting for approximately 45% of European imported gas. In early April, EU Commission President Ursula von der Leyen stated that the commission will present a plan to reduce the EU's reliance on Russian gas, oil, and coal by the middle of May.