KYIV, Ukraine (NewsNation) — Russian President Vladimir Putin claimed victory in Mariupol on Thursday, as he ordered his forces not to storm the city but to block it “so that not even a fly comes through.”

“The completion of combat work to liberate Mariupol is a success,” Putin said in a joint appearance with his defense minister. “Congratulations.”

Ukraine scoffed at the idea that a Russian victory in Mariupol was already achieved.

“This situation means the following, they cannot physically capture Azovstal. They have understood this. They suffered huge losses there,” said Oleksiy Arestovich, an adviser to Ukrainian President Volodymyr Zelenskyy.

Putin’s defense minister, Sergei Shoigu, said earlier Thursday the rest of the city beyond the Azovstal steel plant where Ukrainian forces were holed has been “liberated,” as Russian officials refer to areas of Ukraine they have seized.

However, leaving the plant in Ukrainian hands robs the Russians of the ability to declare complete victory in Mariupol, which has seen some of the most dramatic fighting of the war and whose capture has both strategic and symbolic importance.

Shoigu said the plant was “securely blocked.”

Putin and Shoigu’s comments appeared to reflect a change in strategy in Mariupol, where the Russians previously seemed determined to take every last inch of the city. But it was not clear what it would mean in practical terms. NewsNation will stream the event in the embedded player.

Also Thursday, President Joe Biden is expected to deliver remarks on the monthslong crisis. He is expected to announce additional military aid on top of the $800 million weaponry package approved last week.

Meanwhile, humanitarian corridors have reopened. Four buses with civilians managed to escape from Mariupol after several unsuccessful attempts. Thousands more remain the city, much of which has been reduced to a smoking ruin in a nearly two-month siege, with over 20,000 people feared dead.

Ukraine’s Deputy Prime Minister Iryna Vereshchuk said another attempt to evacuate civilians from Mariupol would be made Thursday , though it was not clear how Putin’s latest comments would affect that.

In Kyiv, Spain’s Prime Minister Pedro Sánchez and Denmark’s Mette Frederiksen became the latest European leaders to show support with a visit to the capital. They were due to meet with President Volodymyr Zelenskyy, who warned in an overnight address that the Russians were not “abandoning their attempts to score at least some victory by launching a new, large-scale offensive.”

“The West stands together to support the Ukrainian people,” Frederiksen, the Danish prime minister, said in a statement.

The Kremlin then claimed it submitted a draft of its demands for ending the war, days after Putin said the talks were at a “dead end.”

Zelenskyy said he had not seen or heard of the proposal, though one of his top advisers said the Ukrainian side was reviewing it.

Kyiv regional police said Thursday that two mass graves with nine bodies were discovered in the city of Borodyanka, northwest of the capital. The findings added to thousands of civilians reported killed by Russian forces, who have been accused of wholesale abuses of Ukrainians.

“I want to stress that these people are civilians. The Russian military deliberately shot civilians that didn’t put up any resistance and didn’t pose any threat,” head of the Kyiv regional police, Andriy Nebytov, said, adding that some of the victims were apparently tortured.

With global tensions running high, Russia reported the first successful test launch of a new type of intercontinental ballistic missile, the Sarmat. President Vladimir Putin boasted that it can overcome any missile defense system and make those who threaten Russia “think twice.”

The Sarmat is intended to eventually replace the Soviet-built missile code-named Satan by NATO. The head of the Russian state aerospace agency called the launch out of northern Russia “a present to NATO.” The Pentagon described the test as “routine” and said it wasn’t considered a threat.

On the battlefield, Ukraine said Moscow continued to mount assaults across the east, probing for weak points in Ukrainian defensive lines. Russia said it launched hundreds of missile and air attacks on targets that included concentrations of troops and vehicles.

The Kremlin’s stated goal is the capture of the Donbas, the mostly Russian-speaking eastern region that is home to coal mines, metal plants and heavy-equipment factories. Detaching it from the rest of Ukraine would give Putin a badly needed victory two months into the war, after the botched attempt to storm the capital, Kyiv.

Russian forces captured 42 villages in the eastern Donetsk region on Thursday, but Ukraine might take them back, an aide to the chief of staff to President Volodymyr Zelenskiy told national television.

“Today 42 villages were added to the list of those that have been occupied. This is at the expense of the Donetsk region,” said the aide, Olena Symonenko. “This happened today and might be that our forces will win them back tomorrow.”

The U.K. Defense Ministry said Russian forces were advancing from staging areas in the Donbas toward Kramatorsk, which continues to suffer from persistent rocket attacks. The Luhansk governor said Russian forces control 80% of his region, which is one of two that make up the Donbas. Before Russia invaded on Feb. 24, the Kyiv government controlled 60% of the Luhansk region.

Gov. Serhiy Haidai said the Russians, after seizing the small city of Kreminna, are now threatening the cities of Rubizhne and Popasna. He urged all residents to evacuate immediately.

Still, Moscow has long demanded Ukraine drop any bid to join NATO. Ukraine said it would agree to that in return for security guarantees from other countries. Other sources of tension include the status of both the Crimean Peninsula, seized by Moscow in 2014, and eastern Ukraine, where the separatists have declared independent republics recognized by Russia.

Earlier this week, Ukraine said the Russians dropped heavy bombs to flatten what was left of the Azovstal steel plant .

A few thousand Ukrainian troops, by the Russians’ estimate, remained in the plant and its labyrinth of tunnels and bunkers spread out across about 11 square kilometers. Zelenskyy said about 1,000 civilians were also trapped.

Russia has repeatedly issued ultimatums to the defenders to surrender, but the Ukrainians have ignored them.

More than 100,000 people overall were believed trapped in Mariupol with little if any food, water, medicine or heat. The city’s pre-war population was 400,000.

A Zelenskyy adviser, Mykhailo Podolyak, said on Twitter that he and other Ukrainian negotiators were ready to hold talks without conditions to save the lives of trapped Mariupol defenders and civilians. There was no immediate response from Russia.

Elsewhere, some residents of the eastern city of Kharkiv have lived in basements for weeks, trying to stay safe from Russian shelling. With no running water, gas or electricity, they collect rainwater and cook on open fires, burning debris from destroyed wooden buildings.

As Russia ushered in new troops, Western nations rushed to boost the flow of military supplies to Kyiv for this new phase of the war — likely to involve trench warfare, long-range artillery attacks and tank battles across relatively open terrain.

Zelenskyy said Ukraine’s Western allies have “come to understand our needs better,” adding that Ukraine is receiving new shipments of Western weapons “now, when Russia is trying to step up its attacks, not in weeks or in a month.”