The Netherlands has been one of the driving forces behind an international coalition to supply Ukraine with F-16s to strengthen its air defence against the Russian invasion.

Denmark, the Netherlands and the United States expect to deliver the first of dozens of F-16s to Ukraine within a few months after establishing the pilot training program and donating aircraft.

"We hope to start this summer and we hope to see the first Dutch planes going there in the autumn," Dutch Defence minister Kajsa Ollongren said after the handover of the planes in Romania.

Ukraine's President Volodymyr Zelenskiy called the donation a "breakthrough agreement" last year and said the planes would strengthen Ukraine's air defences and help its counter-offensive against Russian forces.

But US officials have privately said the jets will not be a game changer when they eventually arrive after months of training, given the strength of the Russian air force and its defence systems.

Russian President Vladimir Putin last month said the F-16s would not change the situation on the battlefield and would be shot down by Russian forces.

"We shouldn't be in this kind of game of saying how much is destroyed because I think that then the Ukrainians have a bigger success than the Russians," Ollongren said.

"The problem is that Russia is continuing this illegal war in Ukraine at the cost of enormous numbers of human lives, also on their side. We have to step up and increase our support to Ukraine."

The Netherlands has already delivered eight of the promised total of 18 F-16s to the training facility since November.

They have also promised to deliver a total of 24 F-16s for use in Ukraine, with the first ones expected to arrive in the second half of the year, adding to earlier deliveries of the aircraft by the Danish armed forces.

Ukrainian officials said on Wednesday three Russian missiles hit the city centre of Chernihiv in the county's north, killing at least 17 people, wounding dozens more and damaging civilian buildings.

Zelenskiy called on Ukraine's allies to rush in air defence support after the city, which had a pre-war population of 300,000, became the latest target of an intensifying Russian air strike campaign.

"This would not have happened if Ukraine had received sufficient air defence equipment and if the world's determination to counter Russian terror had been sufficient," Zelenskiy wrote on the Telegram messaging app.

Videos obtained by Reuters showed flames and columns of black smoke rising over Chernihiv, which is about 150km from the capital Kyiv and about 80km from the Russian border.

Three explosions ripped through a busy central area of the city just after 9am, destroying a hotel, officials said.

The strike also damaged several multi-storey residential buildings, a hospital, an education facility and dozens of private cars, officials said.

"Unfortunately, Russia continues to engage in terrorist activity against civilians and civilian infrastructure as confirmed by this strike on Chernihiv once again," acting mayor Oleksandr Lomako said on television.

Sixty people, including three children, were wounded, the emergency services said.

Russia, which denies targeting civilians, attacked with three Iskander cruise missiles, governor Vyacheslav Chaus told the Suspilne public broadcaster.

Australian Associated Press