KYIV -- Ukrainian President Volodymyr Zelenskiy has threatened to break off talks with Moscow should Russian forces wipe out the remaining Ukrainian soldiers trapped in Mariupol as Moscow claimed it had taken control of the besieged and battered port city after a weeks-long battle.
The Russian Defense Ministry on April 16 said it had cleared the Mariupol urban area of Ukrainian troops and had trapped a few remaining fighters in the Azovstal steel plant, according to Russian state-run media.
A Russian Defense Ministry spokesman was quoted by Russia’s RIA Novosti news agency as saying that Ukrainian forces have lost a total of 4,000 troops during the long fight for the city -- a battle that has caught the world’s attention for its brutality.
Casualty figures from both sides have proved impossible to independently confirm during the conflict, which began with Russia's unprovoked invasion on February 24.
Ukraine has not commented on the latest Russian claims but in recent days has indicated the situation in Mariupol was desperate, with deaths mounting among the trapped civilian population and many experts predicting the city would soon fall to the Russians.
In an interview published earlier on April 16 with Ukrayinska Pravda, Zelenskiy warned Russia against committing atrocities against Ukrainian soldiers in the city.
"The elimination of our troops, of our men [in Mariupol] will put an end to any negotiations,” he said.
"That will bring an impasse as we don't negotiate on either our territories or our people," he added.
Peace talks have taken place between the two sides since Russia's invasion began, with little or no progress.
Ukraine says tens of thousands of people are believed to have been killed in Mariupol, a strategic city that has seen some of the worst fighting of the war.
Reports early on April 16 said heavy fighting continued in several parts of Mariupol as Ukrainian troops attempted to fend off Russian soldiers who have been bolstered by reinforcements in recent days.
"The situation is very difficult [in Mariupol]," Zelenskiy said early in the day. "Our soldiers are blocked, the wounded are blocked. There is a humanitarian crisis.... Nevertheless, the guys are defending themselves."
As the battle for the ruins of Mariupol appeared to be near its bloody end, air-raid sirens could be heard in many other parts of Ukraine on April 16, including in Kyiv, after Russia said it would seek revenge on the capital for what it claimed, without evidence, was Ukrainian targeting of Russian border towns.
Kyiv Mayor Vitali Klitschko said at least one person was killed and several others wounded in early morning attacks.
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"For those Kyivites who left and are already thinking of heading back to return to the capital, I ask you to refrain from this and stay in safer places," Klitschko said in a message on his Telegram channel.
Russian troops have faced tougher-than-expected resistance -- both from the Ukrainian military and from ordinary citizens -- forcing them to retreat from areas in the north and to focus on eastern and southern regions of Ukraine, including Mariupol.
In his nightly address to the nation, Zelenskiy said the success of Ukraine's military and that of international sanctions against Russia will determine how long the war will last.
"The success of our military on the battlefield has been really significant. Historically significant. But it's still not enough to clear our land from the invading forces," he said.
"The sanctions against Russia are very serious, economically painful. But it is not enough to starve Russia's military machine. We need to promote stronger, more destructive sanctions. This will determine how long this war will last," he added.
Russia's warning to inflict more damage on Ukraine came a day after it suffered a symbolic defeat with the loss of its Black Sea fleet flagship, the Moskva, which sank while being towed to port on April 14 after suffering heavy damage under circumstances that remain in dispute.
“The number and the scale of missile attacks on objects in Kyiv will be ramped up in response to the Kyiv nationalist regime committing any terrorist attacks or diversions on the Russian territory,” Russian Defense Ministry spokesman Major General Igor Konashenkov said.
The National Security and Defense Council of Ukraine (RNBO) has rejected Russia’s accusations about the attacks on Russian towns, calling them "an attempt to ignite anti-Ukraine hysteria in Russia."
Kyiv did claim, however, to have hit the Moskva with Neptune anti-ship missiles early on April 14, while Russia said a fire broke out on the ship, causing an explosion.
The U.S. military agreed with the Ukrainian version.
"We assess that they hit it with two Neptunes," a senior Pentagon official said in a briefing with reporters on April 15, calling it a "big blow" for Moscow.
The strikes were believed to have caused casualties, but it was difficult to assess how many, the official said, speaking on condition of anonymity.
The official added that the United States had observed survivors being recovered by other Russian vessels in the area. Russia said the Moskva's crew was evacuated to nearby ships.
Meanwhile, the United States and its Western allies continued to pile pressure on Moscow over its campaign.
The German government said on April 15 that it plans to release more than 1 billion euros in military aid for Ukraine.
The move comes amid criticism from Ukraine and some EU partners such as Poland and the Baltic states that Germany has not done enough to send armaments to Kyiv.
Russia's Foreign Ministry on April 16 said it was banning British Prime Minister Boris Johnson, Foreign Minister Liz Truss, and several other cabinet ministers over British measures aimed at isolating Moscow and crippling the country's economy.
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In Russia, the Federal Security Service (FSB) has asked the government to increase funding for troop funeral services and tombstones.
The FSB asked for a 17 percent increase for funeral services, according to documents recently posted to a government website.
The UN refugee agency said as of April 16 that 4,836,445 million Ukrainians had left the country since the Russian invasion -- up by 40,200 from the previous day’s total.
