One area where there is strong disagreement is missile defense. The United States wants to build a system in central Europe. Russia says that could start a new arms race.

• 双方存在强烈分歧的一个领域是导弹防御问题。美国希望在中欧建立一个导弹防御系统。俄罗斯表示，这可能启动新的军备竞赛。