KYIV/OSLO (Reuters) -- Russia stopped providing gas to Finland in an escalation of a row over energy payments with the West on Saturday, and intensified an offensive in the Donbas region of eastern Ukraine.
After ending weeks of resistance by the last Ukrainian fighters in the strategic southeastern city of Mariupol, Russia is waging what appears to be a major offensive in Luhansk, one of two provinces in Donbas.
Russian-backed separatists already controlled swathes of territory in Luhansk and the neighboring Donetsk province before the Feb. 24 operation, but Moscow wants to seize the last remaining Ukrainian-held territory in Donbas.
The end of fighting in Mariupol, the biggest city Russia has captured so far, could be crucial to that ambition and gives Russian President Vladimir Putin a rare victory.
Ukrainian President Volodymyr Zelensky told local television that while the fighting would be bloody, and victory difficult, the end would come only through diplomacy.
Full control of Mariupol could give Russia command of an overland route linking the Crimea peninsula, which Moscow seized in 2014, with mainland Russia and the areas of eastern Ukraine that are held by pro-Russia separatists.
Despite losing ground elsewhere in recent weeks, Russian forces have advanced on the Luhansk front.
Sievierodonetsk and its twin Lysychansk across the Siverskiy Donets River form the eastern part of a Ukrainian-held pocket that Russia has been trying to overrun since mid-April after failing to capture Kyiv.
Russia’s state gas company, Gazprom, said it had halted gas exports to Finland after it refused to agree to Russian demands to pay for Russian gas in roubles because of Western sanctions imposed over the invasion of Ukraine.
Finland and Sweden applied this week to join the NATO military alliance, a decision spurred by the Ukraine war.
Finnish state-owned gas wholesaler Gasum, the Finnish government and individual gas consuming companies in Finland have said they were prepared for a shutdown of Russian flows and that the country will manage without.
Most European supply contracts are denominated in euros or dollars and Moscow cut off gas to Bulgaria and Poland last month after they refused to comply with the new payment terms.
In addition to trying to isolate Russia through sanctions, Western nations have stepped up weapons supplies to Ukraine.
Kyiv got another huge boost on Saturday when U.S. President Joe Biden signed a bill to provide nearly $40 billion in military, economic and humanitarian aid to the country.