FRANKFURT, Germany (AP) — Fears are rising about what would happen to Europe’s energy supply if Russia were to invade Ukraine and then shut off its natural gas in retaliation for U.S. and European sanctions.

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The tensions show the risk of Europe’s reliance on Russia for energy.

It supplies about a third of Europe’s natural gas, which is already low.

The U.S. has pledged to help fill any shortfall by boosting exports of liquefied natural gas, but there’s only so much it can produce at once.

While no one knows for sure, Russia completely cutting off Europe is viewed as unlikely, because it would be mutually destructive.

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