"If the context is right, I am, of course, also ready to meet with President Putin," he said.
The North Atlantic Treaty Organization has been struggling with myriad conflicts among its members, including US President Donald Trump’s pressure on European allies to pay more for the alliance.
The US president has also softened the anti-Russia stance formerly adopted by NATO.
"Russia is our biggest neighbor, Russia is here to stay, and we need to strive for a better relationship with Russia," Stoltenberg said. "But even without an improved relationship with Russia, we need to manage a difficult relationship with Russia."