NATO needs a 400% increase in air and missile defence to maintain a credible deterrence, its secretary general will say in a speech in London today.

Axar.az reports, citing Sky News, Mark Rutte will call for a "quantum leap" in collective security, warning threats facing the alliance "will not disappear even when the war in Ukraine ends".

It comes ahead of a summit in The Hague later this month, when the UK and its NATO allies are expected to agree to a Donald Trump-inspired pledge to spend 5% of GDP on defence and related areas.

Speaking at Chatham House, Mr Rutte will say the investment plan is "grounded in hard facts".

He will add: "The fact is, we need a quantum leap in our collective defence. The fact is, we must have more forces and capabilities to implement our defence plans in full. The fact is, danger will not disappear even when the war in Ukraine ends".

Mr Rutte will argue that to maintain credible deterrence and defence, NATO needs "a 400% increase in air and missile defence".

"We see in Ukraine how Russia delivers terror from above, so we will strengthen the shield that protects our skies," he will say.

"Our militaries also need thousands more armoured vehicles and tanks, millions more artillery shells, and we must double our enabling capabilities, such as logistics, supply, transportation, and medical support."

On threats against the alliance, he will warn: "Wishful thinking will not keep us safe. We cannot dream away the danger. Hope is not a strategy. So NATO has to become a stronger, fairer and more lethal alliance."