BERLIN 

NATO Secretary General Jens Stoltenberg warned Sunday that the military alliance should be prepared for “bad news” from Ukraine as it continues to face Russia’s war of aggression.

"Wars develop in phases," Stoltenberg said in an interview over the weekend with German public broadcaster ARD, noting: “We have to support Ukraine in both good and bad times.”

"We should also be prepared for bad news," he added, without elaborating.

Stoltenberg defined the war between Russia and Ukraine as "a war of attrition, a battle for efficiency, a battle for logistics."

The ramping up of production by NATO members of ammunition “is vital. We are working hard to ensure that this happens," he added.

Saying that a victory for Russian President Vladimir Putin would not only be a tragedy for Ukraine but also dangerous for the West, Stoltenberg noted that it would be in "our interest" to ensure that Ukraine wins.

“The more we support Ukraine, the faster the war will end,” he added.