headlines:  Russia attacks infrastructure in western Ukraine to slow supply lines 
articles: While tanks and troops exchange fire in Donbas, Ukraine faces another escalating battle on another invisible front line – one that may be equally crucial to determining the outcome of the war.
  
  Russia is stepping up attacks on infrastructure deep into western parts of the country that Moscow has admitted for now it cannot capture, striking targets that keep both the war effort and the national economy running, including the railway network, a critical bridge and fuel depots.
  
  The aim of Russian attacks is likely to slow the rapidly expanding delivery of weapons from Nato allies to the eastern front, while also hindering exports of grain and other commodities that help Kyiv pay for the war. With the country’s Black Sea ports are closed to shipping, overland routes are even more vital.
  
  “It is my opinion that they didn’t believe the west will give Ukraine the necessary heavy weapon supplies so now the process is started, they feel they need to do something about that,” said one Ukrainian military official monitoring the infrastructure attacks. “Because western weapons and Ukrainian combat experience combined give us a big advantage.”
  
  On Monday, five railway stations were hit by Russian missiles. The head of Ukraine’s railways company, Oleksandr Kamyshin, said it was the heaviest assault on his system since the war began. “The repair of all infrastructure damage will take months,” he acknowledged in a news conference.
  
  Fuel depots have been another regular target, along with a critical bridge that provides the only overland link on Ukrainian territory to the southern Bessarabia region.
  
  A spokesman for Ukraine’s defence staff said infrastructure was being hit to stop western arms shipments. “Russians are attacking military and civilian infrastructure to prevent getting weapons from our partners,” Oleksandr Shtupun told a press conference.
  
  Russia’s foreign minister, Sergei Lavrov, said in a broadcast on state TV: “These weapons will be a legitimate target for Russia’s military. Storage facilities in western Ukraine have been targeted more than once. How can it be otherwise?”
  
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  It is not a one-sided battle. A series of destructive explosions and fires at strategic locations inside Russian territory and neighbouring Belarus – fuel depots and railways – are widely considered the work of Ukrainian forces, although none have been claimed officially by Kyiv.
  
  In the early weeks of the war, Ukrainian forces were highly effective at damaging Russian logistics in areas that were contested or recently seized. But in this round of attacks both countries are targeting infrastructure deep inside enemy-held territory.
  
  Senior presidential adviser Mykhailo Podolyak in a tweet about “self-destructing” Russian infrastructure appeared to hint broadly at his country’s role; on the list of destroyed assets he gave was the Moskva ship, widely acknowledged to have been sunk by a Ukrainian missile.
  
  “How can we not believe in karma for the murder of [Ukrainian] children? Many are still willing to turn a blind eye to financing terrorism by buying Russian oil. But should the European Union depend on a country where everything is self-destructing?” he said.
  
  The operations on Russian territory have often been bold and spectacular, boosting morale as much as hindering the enemy’s capacity. They include a daring helicopter raid on the border town of Belograd and Sunday night’s attack on oil storage facilities near a critical crude pipeline junction in Bryansk.
  
  The same night another blast near Bryansk took out a military rail spur used to bring rockets and other munitions from storage onto the main railway network, a Ukraine security source said.
  
  And a powerful radio control tower destroyed in Transnistria, part of Moldova controlled by Russian-backed separatists, was broadcasting propaganda across the region and may also have been used for military communications.
  
  The battle over infrastructure deep inside enemy-held territory is an area where Ukraine may be more vulnerable than Russia because of the size of the country, the extent of Russia’s military resources and the battle for the air.
  
  While not dominant in the skies, it is still easier for Russian planes, drones and helicopters to fly over Ukraine than the reverse and its own skies are largely open, while the government in Kyiv relies entirely on land transport for its military and economic lifelines.
  
  “Rail has always been important [in Ukraine] for exporting things like coal, grain and steel, but it no longer has access to sea ports so a lot more has been going by rail out of the country,” said Tracey German, professor in conflict and security at King’s College London.
  
  “So potentially this isn’t just a way of disrupting the military effort but also of putting pressure on the country economically.”
  
  Russians perhaps did not move strongly against these targets at the start of the war because President Vladimir Putin anticipated a quick victory and perhaps the Russian military thought they would be using the infrastructure themselves.
  
  They also expected to control the skies, which would have made it easier to deny access to roads and railways, said Niklas Masuhr at the Center for Security Studies thinktank in Switzerland. Now there are strong military incentives for a campaign behind front lines.
  
  “The focus has shifted towards the Donbas and there are two underlying drivers of attacks on infrastructure, particularly in western Ukraine. They are potentially trying more to cut off supplies into the Donbas, create a battle of attrition in that part of Ukraine.”
  
  “With strikes on Lviv and Kyiv they may also be trying to hit targets throughout the country, to force them to disperse air defence systems throughout the country, so they don’t have them where needed in the Donbas.”
  
  For Ukraine to win this battle, it needs more air defences for the west, in addition to the heavy weapons and short range air defence systems heading east, the Ukrainian military source said.
  
  “Ukraine on its own cannot protect any inch of its territory from the threat from the air, because Ukraine uses very old aerial defence systems,” the source said.
  
  “Britain is sending short-range things that work great in Donbas. But the strategic thing really necessary for Ukraine is heavy and long-range defence systems to close the skies over [relatively] peaceful areas of the country.”