President Volodymyr Zelensky, who is expected to meet with Rutte, has been appealing to members of the defence bloc for help protecting Ukraine from Russian ballistic missile attacks.

A spokesman confirmed Rutte had arrived along with NATO ambassadors from alliance members after Ukraine's national railway operator posted images of his arrival in Kyiv.

"We are gladly welcoming NATO Secretary General Mark Rutte," Ukrzaliznytsia wrote on social media.

"This visit is extremely important, just like all the previous ones, because it is a gesture of solidarity and support from the Alliance for our country," Ukrzaliznytsia added. The post was later deleted.

His visit comes hours after Ukrainian drones hit energy and military sites in the northern Russian city of Saint Petersburg where officials and visiting dignitaries were gathering for a flagship economic forum.

Russian missile and drone attacks a day earlier killed 23 people in strikes on Kyiv and the eastern city of Dnipro.

Zelensky has been pushing NATO countries to up their deliveries of air defence systems -- in particular US-made Patriot batteries and ammunition, which Kyiv says it needs to shoot down Russian ballistic missiles.