Kyiv (Reuters) – Russia threatened on Tuesday to punish Lithuania with measures that would have a “serious negative effect” on blocking some rail shipments to Moscow’s Baltic Sea region of Kaliningrad in the latest dispute over sanctions over the war in Ukraine.

On the ground in eastern Ukraine, Russia’s separatist proxies said they were advancing toward the main battlefield stronghold of Kyiv. A Ukrainian official described the lull in fighting there as “the calm before the storm.”

On Tuesday, US Attorney General Merrick Garland is expected to become the latest international figure to visit Ukraine, as a Justice Department official said Garland will discuss efforts to prosecute war crimes.

European countries face the prospect that war and sanctions will prompt Moscow to cut gas supplies next winter, and are looking for ways to protect their economies and conserve heat and power. Germany, Russia’s largest energy customer, has revealed details of a new auction system aimed at stimulating the industry to use less gas. Read more

Diplomatic attention has turned toward Russia’s enclave of Kaliningrad, the Baltic sea port and surrounding countryside of nearly a million Russians, connected to the rest of Russia by a railway that runs through EU and NATO member Lithuania.

Lithuania has closed the transport route of steel and other ferrous metals, which it says is required under European Union sanctions that took effect on Saturday.

Russian officials said other essential goods were also banned. Video footage from the pocket showed panic buying over the weekend at stores selling building materials.

Nikolai Patrushev, secretary of the Russian Security Council, visited the enclave on Tuesday to chair a security meeting there. He said Lithuania’s “hostile” actions showed that Russia could not trust the West, which he said had violated written agreements on Kaliningrad.

“Russia will certainly respond to such hostilities,” Patrushev was quoted by the RIA news agency as saying. Without elaborating, he said that “appropriate measures” are being worked out and “their results will have a serious negative impact on the residents of Lithuania.”

Lithuanian Prime Minister Ingrida Simonet said it was “paradoxical to hear speech about alleged violations of international treaties” from Russia, which she accused of violating “perhaps every single international treaty”.

It denied that Lithuania’s actions amounted to an embargo and reiterated Vilnius’ position that it only implements the sanctions imposed by the European Union.

Moscow summoned European Union envoy Markus Eder to the Russian Foreign Ministry on Tuesday. EU spokesman Peter Stano said Eder had asked the Russians at the meeting to “refrain from escalatory steps and rhetoric.”

The standoff creates a new source of confrontation in the Baltic Sea, a region already primed for security reforms that would undermine Russia’s naval power as Sweden and Finland apply to join NATO and bring almost the entire coast under coalition control.

The EU has sought to shift responsibility away from the Lithuanians, saying the policy was a collective action by the bloc. Josep Borrell, the EU’s foreign policy coordinator, said Vilnius “has done nothing but implement the guidelines given by the (European) Commission”.

heavy weight

Inside Ukraine, the battle for the east has become a brutal war of attrition in recent weeks, as Russia has focused its overwhelming firepower on a Ukrainian-controlled enclave in the Donbas region that Moscow claims on behalf of its separatist proxies.

Moscow has made slow progress there since April in relentless fighting that has claimed thousands of soldiers’ lives, in one of Europe’s bloodiest ground battles in generations.

The fighting extended to the Seversky Donets River that runs through the area, with Russian forces primarily on the east bank and Ukrainian forces primarily on the west, although the Ukrainians are still holding out in the city of Severodonetsk on the east bank.

In recent days, Russia has captured the small western bank city of Toshkivka to the south, giving it a potential foothold to try to cut off the main Ukrainian stronghold of Lysichansk.

Rodion Miroshnik, the ambassador to Russia of the pro-Moscow separatist Luhansk People’s Republic, said troops were “moving from the south towards Lysekhansk” with battles raging in a number of towns.

“The coming hours should bring about major changes in the balance of power in the region,” he said on Telegram.

The governor of the Luhansk region surrounding Ukraine said Russian forces had captured some territory on Monday. Serhi Gayday said there was a relative calm at night, but more attacks to come. “It was calm before the storm,” he said.

Although the fighting has favored Russia in recent weeks due to its massive artillery firepower advantage, some Western military analysts say Russia’s failure to achieve a major breakthrough thus far means that time is now on the Ukrainian side.

Moscow is running out of new forces, while Ukraine is receiving newer and better equipment from the West, retired US Lieutenant General Mark Hurtling, former commander of US Ground Forces in Europe, tweeted.

“It’s a heavyweight boxing match,” Hurtling wrote. “In two months of fighting, there hasn’t been a knockout hit yet. It will come, as the Rotian Union’s forces become more and more depleted.”

Dmitry Muratov, editor of Novaya Gazeta, one of Russia’s last independent newspapers, has auctioned off the Nobel Peace Prize he won last year, raising $103.5 million for UNICEF to help Ukrainian refugees. An anonymous buyer presented the medal over the phone at auction in New York. Read more

Novaya Gazeta has halted publication, like all other independent media in Russia, since Moscow imposed a ban on reports that deviate from the official version of the “special military operation” that began in Ukraine on February 24.

(Reporting by Reuters offices) Writing by Peter Graf Editing by Nick McPhee

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