KYIV, Ukraine, July 10, 2024 (BSS/AFP) - Rescue workers cleared debris as Ukraine observed a day of mourning Tuesday, after Russian strikes shattered a children's hospital in Kyiv and sparked international condemnation.

President Volodymyr Zelensky said 43 people were killed across Ukraine by a barrage of nearly 40 missiles that targeted several towns and cities early Monday.

Officials announced a day of mourning in the capital with flags at half-mast and entertainment events postponed, as cranes and first responders worked at the Okhmatdyt paediatric hospital.

Zelensky said rescue work was ongoing at several of the attack sites and that patients from Okhmatdyt had been transferred to other facilities.

"We will restore Okhmatdyt," Zelensky said during his evening address.

The interior ministry said it had completed its search for survivors at the hospital, adding that two people had been killed there and 32 wounded. Eight children were hospitalised, it said.

"At the time of the attack, 627 children were in the hospital," military authorities in Kyiv added.

The president has been urging allies to bolster Ukrainian air defence systems and vowed to renew those pleas after touching down in Washington for the NATO summit.

"We are doing and will always do everything to make the Russian terrorist lose," Zelensky announced in a video statement, saying he would be asking allies for more fighter jets and additional security guarantees during the meeting.

In another speech to a think tank, Zelensky thanked Kyiv's backers for a new air defense package unveiled Tuesday at a NATO summit and urged the United States and others to go further to help defeat Russia.

The attack was roundly condemned by governments across Europe and North America, with Pope Francis voicing "grave sorrow" over the strikes.

Russia also came under fire at the UN Security Council on Tuesday for conducting "systemic attacks" on Ukraine's medical facilities.

"Intentionally directing attacks against a protected hospital is a war crime and perpetrators must be held to account," Joyce Msuya, acting under-secretary for humanitarian affairs, told the emergency meeting.

"These incidents are part of a deeply concerning pattern of systemic attacks harming healthcare and other civilian infrastructure across Ukraine," added Msuya.

Russia currently holds the rotating presidency of the Security Council and its envoy to the United Nations, Vasily Nebenzya, indicated this month he will take a firm line with Ukraine and its Western allies.

- Likely a 'direct hit' -

Hundreds of volunteers gathered at the Okhmatdyt complex on Monday to help clear rubble and search for survivors.

City officials told AFP that the two people killed at the hospital were both adults -- a doctor and a visitor.

Kyiv's mayor said several bodies had been pulled from the rubble of a housing bloc in a central district that was also struck in the attack.

The total killed in the capital was 33 with 117 wounded, according to the latest figures.

Ukraine said a Russian Kh-101 cruise missile had smashed into the renowned children's hospital but Moscow blamed Ukrainian air defence systems.

The Kremlin repeated on Tuesday its claims that Russian forces only target military infrastructure and deferred further questions to the defence ministry.

"We continue to insist that we do not strike civilian targets," spokesman Dmitry Peskov told reporters at a daily briefing.

The UN, however, said there was a "high likelihood" that the children's hospital in Kyiv suffered "a direct hit" from a missile "launched by the Russian Federation".

Danielle Bell, head of the UN Human Rights Monitoring Mission in Ukraine, told reporters a deeper investigation was needed but video footage showed "the weapon directly impacting the hospital".

Russian attacks on Ukraine persisted overnight, with two people wounded in the southern Kherson region and another three hurt in the Zaporizhzhia region, two regions the Kremlin claims are part of Russia.

The Russian defence ministry also said it had captured the village of Yasnobrodivka in eastern Ukraine near the Russian-held city of Donetsk.

The village is the latest in a string of settlements seized in recent weeks, as Ukraine's outgunned and outmanned forces struggle to hold off the advancing Russian forces.