NATO is the "strongest alliance in history" and the United States is committed to its alliances in Europe, U.S. Ambassador to the United Nations Nikki Haley said on February 21.
Washington is working to make the North Atlantic Treaty Organization (NATO) "even more effective," Haley said, and policy differences with European allies should not be seen as anything less than "total commitment to [U.S.] alliances in Europe."
Speaking to the UN Security Council during a debate on conflicts in Europe, Haley said the United States is ready to improve ties with Russia but will not compromise on its support for NATO and the European Union.
Haley said "Russia's attempts to destabilize Ukraine" were among the most serious challenges facing the continent.
"The United States thinks it's possible to have a better relationship with Russia -- after all, we confront many of the same threats," Haley said.
"But greater cooperation with Russia cannot come at the expense of the security of our European friends and allies."
Haley said the United States was committed to "the institutions that keep Europe safe" and that it "will not waver" in its support for the North Atlantic Treaty Organization.
Russia has strongly opposed the expansion of NATO into Eastern Europe, a move which it sees as a policy of containment directed against Moscow.
The United States wants to deepen cooperation within NATO while "keeping the door open to new allies," she said.
Haley's remarks came as European governments are seeking reassurance after U.S. President Donald Trump praised Britain's decision to leave the European Union, and criticized NATO members for failing to spend more on defense.