NATO Official Says Ukraine War Most Dangerous Time In Europe Since World War II

He said Russia must be stopped from winning, and NATO members must support Ukraine for as long as it takes.

"It's in our interest that this type of aggressive policy does not succeed," the former prime minister of Norway said in a speech in his native country. "What happens in Ukraine is terrible, but it would be much worse if there was a war between Russia and NATO."

Russia has referred to the invasion as a "special military operation," though many other countries have called it an act of war. Stoltenberg said it's important that Ukraine prevails to protect the current world order.

This is the most dangerous situation in Europe since World War Two," he said. "If President (Vladimir) Putin even thinks of doing something similar to a NATO country as he has done to Georgia, Moldova or Ukraine, then all of NATO will be involved immediately."

Since the war began, Finland and Sweden have sought NATO membership with instability in the continent. The request has been ratified by 23 of the 30 NATO countries, including the United States.

"This is not just an attack on Ukraine, an independent democratic nation with more than 40 million people, it's also an attack on our values and the world order we want," Stoltenberg said.