Russia accused NATO and the United States of engaging in a proxy war that has created "a serious risk of nuclear war" as Washington convened with its allies on Tuesday at a German air base and pledged to send Ukraine the heavy weapons it needs to resist Russia's invasion.
Russia's top diplomat warned Ukraine not to provoke World War III and said the threat of a nuclear conflict "should not be underestimated" as his country unleashed attacks against rail and fuel installations far from the front lines of Moscow's new eastern offensive.
In a marked escalation of Russian rhetoric, Foreign Minister Sergey Lavrov was asked on state TV about the prospect of World War III and whether the current situation was comparable to the 1962 Cuban missile crisis that nearly caused nuclear war.
"The risks now are considerable," Lavrov said, according to the ministry's transcript of the interview.
"The danger is serious, real. And we must not underestimate it," Lavrov said. "NATO, in essence, is engaged in a war with Russia through a proxy and is arming that proxy. War means war."
Meanwhile, the British Defense Ministry said Tuesday that Russian forces had taken the Ukrainian city of Kreminna in the Lukansk region after days of street-to-street fighting.
"The city of Kreminna has reportedly fallen and heavy fighting is reported south of Izium as Russian forces attempt to advance towards the cities of Sloviansk and Kramatorsk from the north and east," the British military said in a tweet. It did not say how it knew the city, 575 kilometers (355 miles) southeast of the Ukrainian capital, Kyiv, had fallen. The Ukrainian government did not immediately comment.
Ukraine's General Staff said Russian forces were shelling Kharkiv, the country's second-largest city, as they fought to take full control of the Donetsk and Luhansk regions, which comprise the Donbass region in Ukraine's industrial heartland, and establish a land corridor to Crimea.
With Russian forces having been forced back from Kyiv and now attempting a new advance in Ukraine's east, U.S. Defense Secretary Lloyd Austin welcomed officials from more than 40 countries to Ramstein, the headquarters of U.S. air power in Europe.
"We believe they can win if they have the right equipment, the right support," Austin said on Monday in Poland after returning from a visit to Kyiv with Secretary of State Antony Blinken that included discussion of Ukraine’s military needs. He also said the goal is to "see Russia weakened to the degree that it can’t do the kinds of things it has done in invading Ukraine."
U.S. officials have shifted emphasis this week from speaking mainly about helping Kyiv defend itself to talk of a Ukrainian victory that would deliver a blow to Russia's ability to threaten neighbors in the future.
Chairperson of the U.S. Joint Chiefs of Staff Mark Milley, flying to Tuesday's meeting, told reporters the next several weeks in Ukraine would be "very, very critical."
"They need continued support in order to be successful on the battlefield. And that's really the purpose of this conference."
The aim would be to coordinate aid that includes heavy weapons such as howitzer artillery, as well as killer drones and ammunition, Gen. Milley said.
'Bravado'
Kyiv and its allies played down Lavrov's remarks about nuclear war.
Russia had lost its "last hope to scare the world off supporting Ukraine," Ukraine's Foreign Minister Dmytro Kuleba tweeted after Lavrov's interview. "This only means Moscow senses defeat."
British Armed Services Minister James Heappey called Lavrov's remarks an example of "bravado" that had become the Russia's foreign minister's "trademark."
"I don't think that right now there is an imminent threat of escalation," Heappey told BBC Television.
The U.S. State Department on Monday approved the potential sale of $165 million worth of ammunition to Ukraine. The Pentagon said the package could include ammunition for howitzers, tanks and grenade launchers.
Moscow's ambassador to Washington told the United States to halt shipments, warning that Western weapons were inflaming the conflict.
Russia's invasion of Ukraine has left thousands dead or injured, reduced towns and cities to rubble, and forced more than 5 million people to flee abroad.
Moscow calls its actions a "special operation" to disarm Ukraine and protect it from fascists. Ukraine and the West call this a false pretext for an unprovoked war of aggression.
Russia has yet to capture any of Ukraine's biggest cities. Its huge invasion force was forced to pull back from the outskirts of Kyiv in the face of stiff resistance last month. But it has since announced new war aims to focus mainly on the east, and sent more troops there for an assault on two provinces where it has backed a separatist revolt.
"It is obvious that every day – and especially today, when the third month of our resistance has begun – that everyone in Ukraine is concerned with peace, about when it will all be over," Ukrainian President Volodymyr Zelenskyy said late on Monday.
"There is no simple answer to that at this time."
Ukraine's General Staff said on Tuesday that Russia's offensive continued in the eastern Kharkiv region with Russian forces trying to advance towards the village of Zavody.
Russia is probably attempting to encircle heavily fortified Ukrainian positions in the country's east, the British military said in an update on Tuesday.
Reports say the town of Kreminna has fallen, with heavy fighting in the south of the city of Izyum, as Russian forces try to advance towards the cities of Sloviansk and Kramatorsk, Britain's Defense Ministry said on Twitter.
Russian forces kept up their bombing and shelling of the vast Azovstal steel plant in Mariupol where fighters are hunkered down in a city reduced to rubble by Russian siege, Ukrainian presidential aide Oleksiy Arestovych said.