''USA and its NATO and EU allies are pressing Vladimir Putin, to abandon any further invasion of Ukraine''. Stoltenberg

After four hours of talks with Russia, NATO leaders said that they were willing to engage in serious diplomacy with Moscow over arms control and missile deployments in Europe, but they rejected outright Russian demands that the alliance stop enlargement, pull back its forces from member states bordering Russia and guarantee that Ukraine will never join.

''Significant differences'' remained between NATO and Russia, and ''our differences will not be easy to bridge,'' said the NATO secretary-general, Jens Stoltenberg, after the meeting.

''There is a real risk for new armed conflict in Europe,'' Mr. Stoltenberg said, one that would carry severe economic and other costs to Moscow, he added, and would bring about new military deployments in member states near Russia.

The United States and its NATO and European Union allies are pressing Russia’s president, Vladimir V. Putin, to abandon any further invasion of Ukraine, pull back his troops and engage in reciprocal diplomacy on Russia’s security concerns — and NATO’s.