Ukrainian President Volodymyr Zelenskyy pressed Western leaders again on Monday to provide more advanced weapons to help his country in its war with Russia, and he repeated his calls for Russian forces to withdraw from occupied areas of Ukraine, suggesting Christmas as a date to retreat.

During a video conference, Zelenskky told host Germany and other leaders of the Group of Seven industrial powers: “It would be right to begin the withdrawal of Russian troops from the internationally recognized territory of Ukraine this Christmas. If Russia withdraws its troops from Ukraine, then a reliable cessation of hostilities will be ensured.”

He added: “The answer from Moscow will show what they really want there: either a further confrontation with the world or finally an end to aggression.”

The G-7 leaders supported Zelenskyy's appeal, saying in a statement after their meeting that “Russia can end this war immediately by ceasing its attacks against Ukraine and completely and unconditionally withdrawing its forces from the territory of Ukraine.”

The Kremlin has rejected all previous appeals to reverse its land grabs in Ukraine. It didn’t immediately respond to this latest one.

The two countries haven't engaged in any recent peace talks and there is no end in sight for the war, which is in its 10th month and has killed and wounded tens of thousands of people and left dozens of Ukrainian cities and towns in ruins .

Read more: Russia grinds on in eastern Ukraine; Bakhmut ‘destroyed’

Russia has illegally annexed parts of eastern and southern Ukraine, including the Crimean Peninsula in 2014, though it doesn't fully control all of them. Zelenskyy has said his goal is to reclaim all occupied territory, while Russian President Vladimir Putin insists on solidifying his forces' control over the areas.

In his address to the G-7, Zelenskyy echoed his prime minister's Sunday appeal for long-range missiles, modern tanks, artillery and missile batteries and other high-tech air defense systems to counter Russian attacks that have knocked out electricity and water supplies for millions of Ukrainians. He acknowledged that, “Unfortunately, Russia still has an advantage in artillery and missiles.”

Prime Minister Denys Shmyhal told French broadcaster LCI that in addition to making Ukrainians suffer, Russia wants to swamp Europe with Ukrainian refugees by striking power stations and other infrastructure. Zelenskyy told the G-7 that protecting Ukraine's energy facilities from Russian missiles and Iranian drones “will be the protection of the whole of Europe, since with these strikes Russia is provoking a humanitarian and migration catastrophe not only for Ukraine, but also for the entire EU.”

Poland's president, Andrzej Duda, said his nation already has seen an increased demand to shelter refugees.

"The number of refugees in Poland has risen (recently) to some 3 million. That will probably also mean an increase in their numbers in Germany,” Duda said following talks with German President Frank-Walter Steinmeier in Berlin.

Read more: Ukraine: Russia put rocket launchers at nuclear power plant 

On Monday, Russian shelling again mostly focused on eastern and southern regions that Putin illegally annexed.

To defend against further strikes, Shmyhal repeated Ukrainian calls for Patriot surface-to-air missiles — a highly sophisticated system. During the LCI interview, he also asked for more German and French air-defense systems, resupplies of artillery shells and modern battle tanks.

Providing Patriot missiles to Ukraine would advance the kinds of defense systems the West is sending to help the country repel Russian aerial attacks, and would likely mark an escalation.

A U.S. official told reporters the Pentagon has no current plans to send Patriot missiles to Ukraine, but that discussions continue. The key issue is that the complex, high-tech system requires significant maintenance and training, said the official, who spoke on the condition of anonymity to discuss ongoing operations in Ukraine.

Air defenses were also a topic of a phone call Zelenskyy held Sunday with U.S. President Joe Biden. Biden "highlighted how the U.S. is prioritizing efforts to strengthen Ukraine’s air defense through our security assistance, including the Dec. 9 announcement of $275 million in additional ammunition and equipment that included systems to counter the Russian use of unmanned aerial vehicles," the White House said.

The G-7 leaders said in their statement that they've set an “immediate focus on providing Ukraine with air defense systems and capabilities.”

Even with their current systems, Ukrainian forces have already succeeded in intercepting missiles and drones, and a spokeswoman for the country's southern armed forces, Natalia Humeniuk, said Monday on Ukrainian TV that “the effectiveness of anti-aircraft defense is 85%-90%” against weaponized drones.

U.S. officials agree with Ukraine's reported success in shooting down drones and missiles, attributing the high kill rate in part to intelligence that the U.S. and other allies are providing.

Russian drones are still active. Their attacks near the Black Sea port of Odesa over the weekend destroyed several energy facilities and left all customers except hospitals, maternity homes, boiler plants and pumping stations without power.

Slovakia said that in cooperation with Germany, it has opened a center to repair Ukrainian howitzers and air defense systems of Western origin. The center is located inside a military base in the town of Michalovce, some 35 kilometers (22 miles) west of the border with Ukraine, the EU member nation's Defense Ministry said.

In Ukraine, the eastern Donbas region, made up of Donetsk and Luhansk provinces, again has become a focus of intense fighting, particularly around the city of Bakhmut.

Ukrainian officials said Monday the country’s forces hit a hotel in the Luhansk region that served as a headquarters of the Wagner Group, a private Russian military contractor and mercenary group that has played a prominent role in eastern Ukraine.

The region's Ukrainian governor, Serhiy Haidai, said in an unverified claim that hundreds of Russians were killed in the strike on Kadiivka on Sunday. Moscow-backed local officials in Luhansk confirmed that a Ukrainian strike destroyed a hotel building in Kadiivka but claimed it was unused.

Ivan Fedorov, the Ukrainian mayor of the southeastern town of Melitopol, reported that Ukraine attacked a hotel that reportedly housed analysts from Russia’s top security agency, the FSB. Moscow did not comment on that claim, and none of the reports could be independently confirmed. Russian officials, meanwhile, accused Ukrainian forces of blowing up pillars of a bridge in a suburb of Melitopol on Monday night. Various reports said Russian forces had been using the bridge to transport supplies and that traffic across it has now stopped.

Elsewhere, the Ukrainian prosecutor general's office said two civilians were killed and 10 were wounded in Russia’s shelling of the town of Hirnyk in the Donetsk region.

Yaroslav Yanushevych, the governor of the Kherson region, said a Russian strike on the southern city of the same name, which Ukraine reclaimed a month ago, killed two civilians and left five wounded Monday. He said the Russian shelling hit residential buildings and damaged power lines.

And in Skadovsk, about 62 miles (100 kilometers) south of Kherson where the Russian-installed Kherson regional administration had been relocated, a senior government official was lightly injured Monday in an assassination attempt, the Russian Ria-Novosti news agency reported. The driver of a car carrying the official was killed in the attack, it said.