NATO wants a constructive relationship with Russia but for that to happen it must engage Moscow from a position of strength, alliance head Jens Stoltenberg said Tuesday.

The US-led military pact had helped ensure stability in Europe, he said, but now, with its intervention in Ukraine, Russia was "trying to roll back the progress we have made".

Nonetheless, whatever the problems caused, the fact remained that "both NATO and Russia are here to stay. So we simply cannot ignore each other," Stoltenberg told the German Marshall Fund think-tank.

"One way or the other, we will have a relationship. The question is what kind."

Stoltenberg, a former Norwegian premier who took the NATO helm earlier this month with the Ukraine crisis top of the agenda, said his experience proved it was best to deal with Moscow from a position of strength.

NATO membership gave Norway the confidence for a successful relationship with Russia and that was just as true today.

"Only a strong NATO can build a truly constructive and cooperative relationship with Russia," he said, repeating a position he has made several times since taking office.

The Cold War was marked by suspicion, and there "were echoes of that now," he said, but there was an alternative based on mutual respect, on the rule of law and "on common interest, not illusions".

Stoltenberg said NATO wanted a "cooperative relationship with Russia" but Moscow had to want it too and take the steps necessary.

"It is precisely at this time, when our relationship with Russia is the most difficult since the Cold War, that we need to have greater transparency and predictability... to make sure that crises do not spiral out of control," he said.

At the same time, he warned that NATO would not compromise on the principles or values enshrined in the alliance and reiterated its support for Ukraine's sovereignty, independence and territorial integrity.

At a NATO summit last month in Wales dominated by the fallout from the Ukraine crisis, the 28 alliance leaders committed to increase defence spending to two percent of annual economic output within 10 years.

They also approved plans to upgrade NATO's rapid response forces and to rotate forces through the eastern European member states to reassure them that the alliance would stick with them in any new crisis.