By Dan Peleschuk
KYIV, March 25 (Reuters) - Ukraine will aim to repel Russia's new springtime offensive along the front line during a breakdown in U.S.-backed peace talks by building on recent tactical successes and battlefield innovations like mid-range strikes.
The focus of the widely anticipated campaign is the so-called "Fortress Belt" of heavily defended cities in Ukraine's eastern Donetsk region, which Moscow has repeatedly demanded Kyiv relinquish in return for peace.
Over the last week, Russia
has launched a battalion-size assault northeast of Sloviansk, the belt's northern anchor, and smaller attacks near the cities of Pokrovsk and Kostiantynivka, on its southern end, seeking to create conditions for a broader offensive, the U.S.-based Institute for the Study of War (ISW) said.
Authorities in Sloviansk announced on Friday the evacuation of children from the city as Russian forces advanced just 20 km east - a sign of the deteriorating security situation.
Though Russian forces outnumber Ukraine's, improved tactical assaults by Kyiv and its evolving drone strike capability could slow Moscow's gains, said Rob Lee, a senior fellow at the Foreign Policy Research Institute, a Philadelphia-based think tank.
"Russia still has enough manpower to keep advancing this year," said Lee. "How far they're going to get is an open question."
Kyiv's forces enter spring having clawed back some territory on the southeastern front in a rare battlefield win last month - helped on by Elon Musk's crackdown on Russia's use of his Starlink internet service which has disrupted its military communications.
Ukraine said it has begun eliminating more troops than Russia is recruiting, a key part of new Defence Minister Mykhailo Fedorov's technology-driven, metrics-focused war plan. Russia dismisses Ukrainian claims about its losses.
The intensification in fighting comes as war in Iran has diverted U.S. attention away from its mediation of peace talks and has replenished Russia's state coffers thanks to a jump in oil prices.
The Middle East war is also draining supplies of U.S. air-defence weapons that Ukraine relies upon to defend its cities, energy infrastructure and military sites.
Meanwhile, Ukraine's finances look precarious after Hungary blocked a 90 billion euro EU loan this month, and the military is still struggling to recruit enough soldiers for the front.
MULTI-FRONT BATTLE
Russia's grinding winter gains included nearly all of the former eastern logistics hub of Pokrovsk, where Ukrainian officials said Moscow lurched forward at great human cost.
Yevhen Lasiychuk, commander of Ukraine's 7th Rapid Response Corps overseeing the sector, said there were no immediate signs that Russia was massing for a major new assault there.
Instead, he added, any push for the Fortress Belt would likely combine attacks around Pokrovsk with sieges of nearby Kostiantynivka and Sloviansk in order to "shake" multiple axes.
"They'll try to break our battle formations, rupture them where there's a weak point, and then exploit that," Lasiychuk said in a recent interview.
"The tactics haven't changed - we understand them."
President Volodymyr Zelenskiy said on Sunday that Russia was taking advantage of warmer weather to intensify its offensive efforts.
Ukraine's General Staff said Russian forces had carried out more than 600 assaults over four days last week on several parts of the front line - including 163 near Pokrovsk and 84 near Kostiantynivka.
Valery Gerasimov, the chief of Russia's General Staff, said last week that Moscow's offensive was "underway in all directions" and aimed at the cities of Sloviansk, Kramatorsk and Kostiantynivka.
Emil Kastehelmi of Black Bird Group, a Finland-based security and intelligence analysis team, said recent attacks in northern Donetsk had involved a significant number of armoured vehicles, whose use has been made rarer by their vulnerability to drone attacks.
That was a sign that Russia was looking to punch through the front line and increase the pace of its gains, he added.
"Generally, it hasn't been successful," Kastehelmi said, adding that drone dominance of the battlefield had neutralized armoured advances. "Russia will probably continue advancing a few hundred square kilometres per month, but the general dynamics, I don't see them changing."
ISW, in a recent report, said it also expected to see only "some tactical gains" by Russia around the Fortress Belt in 2026, rather than a major breakthrough.
In the southeastern Zaporizhzhia region, Moscow's troops are crawling forward across lowlands around 70 km east of the regional capital. There, Kyiv faces the daunting task of defending swathes of open land, unlike the densely packed cities of the east.
"Zaporizhzhia is the steppe ... where there are no geographic obstacles that might hinder the enemy's advance or allow us to hide easily," said Oleh Shyriaiev, commander of the 225th Separate Assault Regiment, whose unit was deployed around the strategic town of Huliaipole this winter to help stem sudden Russian advances.
Russian troops are also attempting to press through a narrow corridor just 20 km south of heavily industrialised Zaporizhzhia city.
MODEST GAINS AND MID-RANGE STRIKES
Ukrainian battlefield advances last month, which the government said totalled around 400 sq km, were modest but sent a clear message to Russia, said Vladyslav Urubkov, head of the military department at Come Back Alive, a leading Ukrainian charity which helps equip the army.
For the first time since summer 2024, Kyiv's troops regained control over more territory last month than Russian forces captured, Ukrainian officials said. Russia says it captured 6,000 sq km overall in 2025.
"It reminds them that they are not (an) absolute power and they have also weaknesses, and we see those weaknesses and we can use them," said Urubkov, citing what he said was low morale and poor training of Russian troops.
He added that Kyiv would need to concentrate larger, well-prepared forces if it wanted to achieve bigger breakthroughs elsewhere.
Lee, the FPRI fellow, said Ukraine's counterattacks were driven largely by battle-hardened units whose integration of drones during assaults could offer broader lessons in exploiting Russian gaps.
Kyiv's intelligence services, together with its Unmanned Systems Forces, have meanwhile stepped up long-range strikes on strategic Russian targets like oil depots and refineries, as well as weapons and missile manufacturing sites.
Ukraine is also expanding its mid-range drone strike abilities, allowing battlefield units like those in Lasiychuk's sector to target personnel and, critically, logistics at a distance of 50 km or more.
"It doesn't matter whether it's an ammunition depot or food storage - both are critical targets," Lasiychuk said. "A soldier won't fight without food."
He added that new coordination among drone units in his corps has also allowed forces to plan better and assign targets more efficiently.
(Additional reporting by Daniel Flynn; Editing by Andrew Cawthorne)
