European officials have slammed Russia’s decision to limit natural gas exports to Poland and Bulgaria as “blackmail,” claiming that the cutoff, as well as the Kremlin’s threat to stop shipments to other countries, is a failed attempt to split the West over its support for Ukraine.

Russia’s decision to use its most important export as leverage on Wednesday signified a major escalation in the economic war of sanctions and countersanctions that has been going on in the background while the combat on the front has been going on.

The strategy used against the two EU and NATO members may eventually force the targeted countries to ration gas, dealing yet another blow to economies already reeling from rising costs. At the same time, it risks depriving Russia of vital funds for its military effort.

Poland has been a significant conduit for the sale of arms to Ukraine, and it announced this week that it will be deploying tanks to the nation. Poland issued fresh sanctions against Gazprom and other Russian corporations and billionaires only hours before Russia’s national energy behemoth responded.

Bulgaria has severed many of its previous relations with Moscow under a new liberal administration that took office last November, and it has also backed punitive measures against the Kremlin. Western fighter planes have also been stationed at a new NATO facility on Bulgaria’s Black Sea coast.

The gas restrictions do not put the two countries in immediate jeopardy. Poland, in particular, has been striving for years to secure alternative supplies, and the continent is approaching summer, making gas less of a need for families.

Furthermore, Russian gas exports to Poland and Bulgaria were set to halt later this year.

Nonetheless, the shutdown and a threat from the Kremlin that other nations may be next sent shivers down the spines of the European Union’s 27 members. Germany is the world’s largest importer of Russian energy, and Italy is a substantial user as well, but both countries are working to minimize their reliance on Moscow.

“It’s no surprise that the Kremlin is attempting to blackmail us with fossil fuels,” said EU Commission President Ursula von der Leyen. “Today, the Kremlin’s attempt to create dissension among member nations failed once more. In Europe, the age of Russian fossil fuels is coming to an end.”

The two countries were cut off by Gazprom because they refused to pay in rubles, as President Vladimir Putin asked of “unfriendly” countries. If other nations do not agree to the payment system, the Kremlin has threatened to cut them off.

Russia’s demand for rubles has been met with resistance from European countries. Moscow has recently offered a method that it claims meets its needs, but which the Europeans claim means they will continue to pay in euros or dollars.

“Europe (and) Germany will make payments in euros, while others may pay in dollars,” German Economy Minister Robert Habeck said on Wednesday. “Gazprom is responsible for the conversion once the funds have been completed. We’ve talked about it with the European Union. We’ll keep going in this direction.”

Mateusz Morawiecki, Poland’s prime minister, informed his country’s parliament that the gas shutdown was caused by Poland’s support for Ukraine, as well as fresh sanctions imposed by Warsaw on Tuesday.

“We will not submit to such a scam,” Bulgarian Prime Minister Kiril Petkov said of the suspension.

Russia, according to Ukrainian President Volodymyr Zelenskyy, sees gas as a tool for political blackmail and “sees a united Europe as a target.”

Fighting raged in the country’s east along a mostly static front line stretching for 300 miles (480 kilometers).

Russia claimed that their missiles targeted a shipment of weaponry provided to Ukraine by the United States and European nations. Rockets hit a residential neighborhood in Kharkiv, killing one person and injuring at least two more.

Russia has made gradual progress in the eastern Donbas area, according to Western sources who spoke on the condition of anonymity to discuss intelligence findings, with “minimal victories” including the takeover of villages and small towns south of Izyum and on the outskirts of Rubizhne.

The governor of the Luhansk area, Serhiy Haidai, admitted that Russia has made some progress on Rubizhne through its near-constant shelling, but that Ukrainian soldiers are fighting back and retiring only when there is nothing left to defend.

“It’s pointless to stay on land that’s been fired on so many times that every meter is well recognized,” he remarked.

Maxim, a Donbas-based Ukrainian tank commander who declined to reveal his last name, explained why Ukrainian forces had been able to fend off the better-equipped Russian army: “It’s not the tank that gives you strength; it’s the people who give you strength.”

Some Russian forces have been relocated from the destroyed southern port city of Mariupol to other sections of the Donbas, according to Western authorities. However, some people remain in Mariupol to resist Ukrainian soldiers stationed at the Azovstal steel complex, the city’s last stronghold. An estimated 2,000 Ukrainian defenders and 1,000 civilians were supposed to be seeking refuge there.

“It’s a tricky scenario.” In a Facebook video message, Serhii Volynskyi, commander of the marine unit inside the factory, stated, “There are big difficulties with water and food.” Hundreds of combatants and civilians were wounded, according to him, and those inside included children, the elderly, and the crippled.

A series of explosions erupted late Wednesday near the television tower in the Black Sea port city of Kherson, which Russian forces have seized since the beginning of the conflict, knocking Russian networks off the air at least briefly, according to Ukrainian and Russian news agencies.

An ammo dump in the Belgorod district, just across the Russian border from the Donbas, caught fire after numerous explosions, according to the governor. Blasts were also reported near the border in Russia’s Kursk area, while officials in Russia’s Voronezh district said a drone was shot down by an air defense system.

An oil storage facility in the Russian city of Bryansk was destroyed by fire earlier this week.

Mykhailo Podolyak, a Ukrainian presidential adviser, alluded to the country’s role in the flames in a Telegram post, adding that “karma (is) a severe thing.”

Ukrainian soldiers were able to prevent Russian forces’ attempt to storm Kyiv with the support of Western weapons. Moscow now claims to be concentrating its efforts on capturing the Donbas, Ukraine’s primarily Russian-speaking industrial heartland.

“All the duties of the extraordinary military operation we are undertaking in the Donbas and Ukraine, began on February 24, will be absolutely accomplished,” Putin told lawmakers.