(BSS/AFP) - More than 50 people could be trapped under rubble in a Ukrainian village where a Russian attack killed 33 people, President Volodymyr Zelensky said Tuesday, in what he called one of Moscow`s worst attacks of the war.

Russia pummelled Ukraine on Monday and Tuesday after a rare truce between the enemies ended at the weekend, with the strikes dampening hopes for a breakthrough at US-led negotiations set for next week in Abu Dhabi.

Rescue operations were ongoing in the frontline southeastern village of Komyshuvakha, where Russian forces had struck a former school building that Ukraine said was being used to distribute aid every Monday.

"Just one strike killed 33 people. Five people were rescued and more than 50 may still be trapped under the rubble," Zelensky said, describing it as "one of the largest Russian killings of this war".

The United Nations` right mission in Ukraine slammed the attack.

"Either the Russian armed forces knew that there was a humanitarian distribution taking place, or they failed to take the most basic steps to find out what was happening in this village," said Danielle Bell, the head of the rights mission.

The attack hit hours after a ceasefire held for several days in the Kherson region, allowing for a rare humanitarian mission.

A Russian strike on a hospital in Kharkiv also wounded dozens Tuesday, Zelensky said, with Ukrainian authorities reporting another four dead across the country.

Zelensky, the Kremlin and Washington confirmed their negotiators will meet in Abu Dhabi on November 10-11 for the first talks between all three sides since February.

Visiting Berlin on Tuesday, Zelensky said he hoped that the gathering will pave the way for his meeting with Russia`s Vladimir Putin.

"We are counting on the fact that work in this format and our other diplomatic steps will open the way to a trilateral format at the level of leaders," he told reporters.

Zelensky has consistently pushed for a meeting with Putin -- who sent Russian troops over the border in 2022, unleashing Europe`s worst war since World War II.

Putin, however, has repeatedly refused face-to-face talks with Zelensky.

Speaking alongside Zelensky, German Chancellor Friedrich Merz said he saw no sign that Russia was willing to engage seriously in ending its invasion.

"It is important that Russia finally and seriously engages in negotiations about a ceasefire and a subsequent peace agreement," he said.

"I do not see that happening so far."

- `Ukraine must be at the table` -

Kyiv and its European allies have feared US President Donald Trump -- who signed a diesel deal with Putin recently and who has criticised Zelensky -- is siding with the Kremlin.

Merz said that if Trump invites Putin to the G20 summit in Miami then Zelensky should be invited, too.

"If Ukraine is to be discussed, then the president of Ukraine must be at the table."

Last week`s ceasefire in Kherson -- brokered by US First Lady Melania Trump -- had provided a glimmer of hope that a negotiated end to the conflict could be on the horizon.

Zelensky said Kyiv had offered Russia an extension of the ceasefire, but shortly afterwards Moscow unleashed deadly strikes.

"We proposed to Russia to prolong and expand the ceasefire," Zelensky said.

"But in response, we got this, this kind of attack. New shelling, new strikes, new killings."

Merz said that while the Kherson ceasefire could have served as "a model" for other truces, "Russia has so far stubbornly refused this."

- Talks in Brussels -

"Our message to Russia is therefore clear: it is time to bring this war to an end," Merz, who leads one of Ukraine`s main military and financial backers, said.

Putin has repeatedly said Russia does not want a temporary ceasefire in Ukraine and that Moscow intends to seize the rest of east Ukraine by force.

Repeated Russian strikes on Ukraine`s energy infrastructure in recent weeks have raised fears of another difficult winter ahead, and on Tuesday Kyiv mayor Vitali Klitschko said supplies in the capital were "extremely difficult".

Trump`s special envoy Steve Witkoff said US negotiators would also meet European and NATO officials on Wednesday in Brussels.

Representatives from Ukraine, the United States, France, Germany, Britain, NATO and the World Bank will take part, the European Commission said.

In Russia, Moscow mayor Sergei Sobyanin said nearly 500 drones heading towards the capital region were destroyed.

The strikes came as Britain and France announced that around 2,800 troops from 10 European countries will stage military drills in Poland this month in support of Ukraine.