The following is an extract from the interview.

Deutsche Welle: How can the NATO alliance make it very clear to Russia that it cannot win this war?

Jens Stoltenberg: The quickest way of ending a war is to lose the war. But that will not bring peace. That will bring occupation, and occupation's not peace. So the challenge in Ukraine is to end the war in a way where Ukraine prevails as a sovereign, independent nation. And then we're back to the basic message. Putin's aim is to control Ukraine. We cannot change his mind, but we can change his calculus, and the way to do that is to make the Ukrainians stronger on the battlefield, so he realizes that he cannot achieve his goals on the battlefield but has to sit down and negotiate a lasting peaceful agreement.

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