Ben Barry, senior fellow for land warfare at the International Institute of Strategic Studies, said: “The attack will have been supported by artillery and rocket launchers inside Russia.
Ukraine’s targets: Artillery, tanks and airfields
“So not being able to engage with western supplied long-range weapons, things like GMLRS [Guided Multiple Launch Rocket System] and Atacms make it much more difficult to deal with those targets. It’s really simple.”
Andriy Zagorodnyuk, a former Ukrainian defence minister, said: “Regarding what they are going to strike, it is also quite simple: simple equipment, artillery units, tanks, etcetera, but also, but also the larger targets such as some command and control posts, if they know where they are and logistics you know, airfields.
“When I say logistics it means like rail cars which carry heavy vehicles, tanks and so on, that are transported by rail and then unloaded. The same kind of thing they would strike in occupied Donbas or Crimea.”
The immediate focus will be on the 20-mile stretch of countryside between the city of Belgorod and the border from which the latest Russian offensive launched on May 10.
Rob Lee, a senior fellow at the foreign policy research institute, a US think tank, said American-supplied Himars and European artillery will likely prioritise Russian artillery and launch sites for Lancet attack drones.
These launch sites have been enjoying considerable success and able to operate largely with impunity from inside Russia, he said.
Ukraine could also preemptively target a large Russian force that has been spotted mustering around the village of Graivoron, about 30 miles further west. It is feared that the force may be preparing for an attack on the Sumy region.
Further afield, several airbases will come within range of British and French storm shadow missiles. The Baltimor airbase at Voronezh, home to a Russian SU-34 squadron, is probably the most significant of those possible targets.
The Ukrainians have also been given permission to use air defence missiles to shoot down enemy aircraft which pose a threat. Given the shortage of air defence missiles and the near impossibility of intercepting glide-bombs in flight, destroying aircraft on the ground may, however, be the only realistic way to challenge Russia’s increasing dominance of the skies.
There is still some confusion over the remaining restrictions on Ukraine’s army. After the news of Biden’s reversal broke on Thursday, one White House official said that the policy in terms of using long-range Atacms missiles “has not changed”.
That might mean that the White House has authorised GMLRS but not Atacms strikes across the border. But even that would make a difference.
“Yes, Russia does degrade [GMLRS] accuracy with electronic warfare jamming, they have become a little less accurate [since they arrived in 2022]. But they have played a very important role for Ukraine, and Ukraine is an artillery-centric army,” said Mr Lee. “If they can’t use this kind of really important ground-based fires capability it affects how Ukraine fights.”
The rapid adjustment of long-standing Western policy follows mounting anxiety about Russian offensives this summer. The attack on Kharkiv forced Ukraine to redeploy forces from what is thought to be the central Russian effort in Donbas. However, so far, that does not appear to have enabled a major Russian breakthrough.
Putin’s response
Vladimir Putin claimed last week that using precision western weapons for long range strikes inside Russia would amount to a Nato attack on Russia and could warrant an appropriate response.
Nato countries, especially smaller ones, should remember that “as a rule they have small territories with very dense populations,” the Russian president said. “That’s a factor they should keep in mind before talking about strikes deep in Russian territory.”
Dmitry Suslov, a member of the Moscow-based Council for Foreign and Defence Policy think tank, on Wednesday called for a “demonstrative” nuclear weapons test to deter the West from lifting the strike restrictions.
Asked about those threats, Mr Stoltenberg said on Friday: “This is nothing new. It has … been the case for a long time that every time Nato allies are providing support to Ukraine, President Putin is trying to threaten us to not do that,” he told reporters on Friday.
“And an escalation – well, Russia has escalated by invading another country.”
Keir Giles, fellow of the Russia and Eurasia Programme at Chatham House, believes Russia’s current nuclear rhetoric is a long way below the threshold of genuine threat.
“I’ve sat next to Suslov at a Nato conference. He’s been saying this kind of thing for years – since long before the full scale invasion.”