He complained that the European countries now had too few weapons, equipment and soldiers in a state of high readiness for a potential conflict, TASS reported.
"We know that we are behind (the Russians)," he said. "I can't tell you exactly how much it will cost (to compensate for the lagging behind.) But I can tell you with certainty that if allies are going to deliver on the capabilities they have promised it will cost much more than 2 per cent, whether it's 2.5 or 3."
According to Stoltenberg, Moscow is also aware of this state of affairs.
Asked what he regretted most after leaving his post as the alliance’s secretary general, Stoltenberg said NATO should have started supplying lethal weapons to Ukraine earlier. He argued that the deliveries should have been carried out before the start of war in February 2022, but most allies "were very afraid of the consequences."
If Stoltenberg is to be believed, the availability of more modern weapons to Ukraine could have prevented a conflict with Russia or "at least made it much harder" for the Russian army to carry out combat missions.
"If there's anything I in a way regret and see much more clearly now is that we should have provided Ukraine with much more military support much earlier," he said. "I think we all have to admit, we should have given them more weapons, more advanced weapons, faster. I take my part of the responsibility."