Russia could attack a NATO country within the next five years, the Secretary General of NATO, Mark Rutte, said in a stark new warning.
"NATO's own defences can hold for now," Rutte warned in Berlin, but conflict was "next door" to Europe, and he feared "too many are quietly complacent, and too many don't feel the urgency, too many believe that time is on our side.
"Russia is already escalating its covert campaign against our societies," Rutte said in a speech in Germany. "We must be prepared for the scale of war our grandparents or great-grandparents endured."
Earlier this month, Russia's President Vladimir Putin said his country was not planning to go to war with Europe, but it was ready "right now" if Europe wanted to - or started a war.
But similar reassurances were given by Moscow in 2022, just before 200,000 Russian troops crossed the border and invaded Ukraine.
Putin has accused European countries of hindering US efforts to bring peace in Ukraine - a reference to the role Ukraine's European allies have recently played in trying to change a US peace plan to end the war, whose initial draft was seen as favouring Russia.
But Putin was not sincere, NATO's secretary-general said in the German capital, Berlin.
Supporting Ukraine, he added, was a guarantee for European security.
"Just imagine if Putin got his way; Ukraine under the boot of Russian occupation, his forces pressing against a longer border with NATO, and the significantly increased risk of an armed attack against us."
Russia's economy has been on a war footing for more than three years now - its factories churn out ever more supplies of drones, missiles and artillery shells.
According to a recent report by the Kiel Institute for the World Economy, Russia has been producing each month around 150 tanks, 550 infantry fighting vehicles, 120 Lancet drones and more than 50 artillery pieces.
The UK, and most of its Western allies, are simply not anywhere near this point.
Analysts say it would take years for Western Europe's factories to come close to matching Russia's mass-production of weapons.
"Allied defence spending and production must rise rapidly, our armed forces must have what they need to keep us safe," the Nato chief said.
