European Commission chief Ursula von der Leyen said Wednesday that the 27-nation European Union needs to make emergency plans to prepare for a complete cut-off of Russian gas in the wake of the Kremlin’s war in Ukraine.

The EU has already imposed sanctions on Russia, including on some energy supplies, and is gearing away from Kremlin-controlled deliveries. But the head of the EU’s executive branch said the bloc needed to be ready for shock disruptions coming from Moscow.

She said a dozen members have already been hit by reductions or full cuts in gas supplies as the political standoff with Moscow over the Ukraine invasion intensifies.

“It is obvious: Putin continues to use energy as a weapon. This is why the Commission is working on a European emergency plan,” she said. “We need to make sure that in case of full disruption, the gas flows towards where it is most needed. We have to provide for European solidarity.”

European Union countries already agreed last month that all natural gas storage in the 27-nation bloc should be topped up to at least 80% capacity for next winter to avoid shortages during the cold season. The new regulation also says underground gas storage on EU soil will need to be filled to 90% capacity before the 2023-24 winter.

The war in Ukraine has prompted the 27-nation bloc to rethink its energy policies and sever ties with Russian fossil fuels. Member countries have agreed to ban 90% of Russian oil by year-end in addition to a ban on imports of Russian coal that will start in August.

The EU has not included gas — a fuel used to power factories and generate electricity — in its own sanctions for fear of seriously harming the European economy. Before the war in Ukraine, it relied on Russia for 25% of its oil and 40% of its natural gas.

To slash its use of Russian energy, the European Commission has been diversifying suppliers.

“And our efforts are already making a big difference,” von der Leyen said. “Since March, global LNG exports to Europe have risen by 75% compared to 2021. LNG exports from the U.S. to Europe have nearly tripled.”

In the meantime, the average monthly import of Russian pipeline gas is declining by 33% compared with last year, von der Leyen said as she called for a speedy transition toward renewable sources of energy.

“Some say, in the new security environment after Russia’s aggression, we have to slow down the green transition. This transition would come at the ‘the cost of basic security’, they say. The opposite is true. If we all do nothing but compete about limited fossil fuels, the prices will further explode and fill Putin’s war chest,” she said. “Renewables are home-grown. They give us independence from Russian fossil fuels. They are more cost-efficient. And they are cleaner.”

The EU Council agreed last month to raise the share of renewables in the bloc’s energy mix to at least 40% by 2030 — up from the previous target of 32%. In addition, a 9% energy consumption reduction target for 2030 will become binding on all EU member states for the first time.