NATO Secretary General Jens Stoltenberg says NATO leaders on December 3-4 in London will discuss a united approach to Russia's destabilizing activity.

We agree that NATO is the only guarantor of European security. Our forces prevent conflict and preserve peace. They send a clear message of NATO's commitment to the Baltic region in the face of Russia's military buildup and pattern of destabilizing behavior. We will discuss our unity, united approach to Russia at the meeting of NATO leaders in London next week," Stoltenberg said at a joint briefing with Latvian President Egils Levits in Brussels Monday.

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The secretary general also said that "the foundations of NATO are strong and we will ensure our Alliance is fit for the future."