At least 1,200 rockets, including ballistic missiles, and 1,500 Iranian-made Shahed drones had been launched by Russian forces since the beginning of the year, he added.
In a stark warning over support for Ukraine, Mr Zelensky accused Nato of not doing enough to counter Russian aggression against his country.
“Dear friends, the world has seen so far an alliance that does not have equals in countering terror,” he said.
“Israel was not left alone and almost 100 per cent of the strikes against it were neutralised. It’s a convincing efficiency of the air shield of Nato countries… your air defence, your combat aviation, everything that now works in the skies of the Middle East and [against] not only Iranian drones and rockets but also several dangerous myths, especially the myth that Nato members’ actions in defence of a third country from drones and rockets involves Nato in the war.”
Western governments have refused since the early days of the war in Ukraine to directly intervene and shoot down Russian-fired missiles and drones amid fears doing so would lead to direct confrontation with Moscow.
In recent months, Russia has stepped up its long-range campaign against Ukrainian energy infrastructure, leading to fears the war-torn nation may soon struggle to generate its own power.
Mr Zelensky earlier this week revealed missiles had struck and destroyed a vital power plant on the outskirts of Kyiv because his forces had run out of air defence ammunition.
Ukraine is calling for both the Patriot and Franco-Italian Samp/T system, each of which are known to be successful in countering Russian ballistic missiles.
Mr Stoltenberg said there were many Nato allies that didn’t operate either system but had pledged money to help buy them for Ukraine.
British defence sources would not speculate on whether the UK would contribute financially to such an effort. The British military does not operate either system.
It is thought to be more likely that the Government will donate another batch of ASRAAM short-range air-to-air missiles, which are manufactured in the UK and designed to be fired from Typhoon fighter jets, but converted to be fired from the ground by the Ukrainians.
A Ministry of Defence spokesman said: “The UK is fully committed to providing further air defence systems for Ukraine – we have delivered nearly 2,000 air defence missiles, with the most recent package of around 200 missiles announced at the end of 2023 and delivered in recent months.”
Germany last week pledged its third Patriot battery to Ukraine, and launched an initiative to find more countries willing to donate their systems to Kyiv.
Mr Stoltenberg said Nato officials had mapped all of the air defence systems available to the alliance and said there were spare Patriots that could be donated to Ukraine without compromising its security.
“There are systems that can be made available to Ukraine,” he told reporters.
