SLOVIANSK, Ukraine — At one point on the front line, Ukrainian soldiers advanced by creeping on their bellies 50 yards at a time, digging new trenches at every stop. Elsewhere, soldiers with the 93rd Brigade captured about three miles of wheat fields — and a Russian tank. Another unit liberated a village last week.
Out on the rolling plains of eastern Ukraine’s eastern Donbas region, soldiers and commanders are pointing to these modest gains as a measurable result of Ukraine’s strategy of publicly, and frequently, making its intentions known to attack Russian forces along another front: southern Ukraine.
The Russian Army, Ukrainian officials and Western analysts say, has been diverting soldiers to the south to meet a potential offensive — allowing Ukraine to regain slivers of land in the east.
But after a summer of feints and maneuvering with few conclusive battles, both sides now face a quandary over how to concentrate their forces, leaving commanders in a guessing game about where, when and how their enemy might move.
“We have reached a situation of parity,” in the war in eastern Ukraine, said Yuriy Bereza, the commander of the Dnipro-1 unit in Ukraine’s National Guard, which is fighting outside the eastern city of Sloviansk
Mr. Bereza credited the appearance on the battlefield, beginning about a month ago, of American-supplied High Mobility Artillery Rocket Systems, with quieting Russia’s artillery. The systems, known as HIMARS, can strike with precision far behind Russian lines.
“The first time I heard a HIMARS launch it was like music to my ears,” Mr. Bereza said. “It is the most beautiful music for Ukrainian soldiers.”
The United States announced on Monday $1 billion in additional military aid, including more HIMARS rockets, 95,000 artillery shells, 1,000 Javelin antitank missiles and more. It is the single largest package of weaponry yet for Ukraine, bringing the total to $9.8 billion in the past year and a half, most of it since the Russian invasion in February.
American officials have also cited the HIMARS as making a difference, but with everything in this war, much remains opaque: Rumors run rampant, propaganda is pervasive, and both Ukraine and Russia are quick to tout advanced weapons — like the HIMARS — while keeping operational details secret.
Some analysts say Russia’s slowdown in the east has less to do with splitting its attention or Ukraine’s weapons than with a need to rebuild and redeploy its battered forces.
Our Coverage of the Russia-Ukraine War
The Pentagon highlighted that problem in a news briefing on Monday, where Colin Kahl, under secretary of defense for policy, estimated that 70,000 to 80,000 Russian troops had been killed or wounded since the invasion began, a staggering loss that exceeds the official U.S. military casualty counts in the long wars in Afghanistan and Iraq combined.
Western military analysts have reported the diversion of Russian forces and a reduction of violence and artillery fire in the Donbas, which had been Russia’s focus since it failed to capture Kyiv, the capital, in the spring.
Since then, Russia’s war in Ukraine has effectively divided into two theaters, the east and the south, with Ukraine seeking to slow or stop Russian advances in the east while counterattacking in the south.
The Russians are most vulnerable, in Ukraine’s view, on territory they hold on the western bank of the broad Dnipro River, primarily in Kherson province. In recent weeks, the Ukrainian military has struck two bridges used for resupply, and on Saturday hit them again.
Russian forces have been reinforcing positions in the south, Britain’s Ministry of Defense said in a recent assessment, as “Ukrainian forces are focusing their targeting on bridges, ammunition depots and rail links with growing frequency.” The reinforcements could defend, or pre-empt Ukraine’s attack with an offensive of their own.
The assessment cited “long convoys of Russian military trucks, tanks, towed artillery, and other weapons” moving from the Donbas toward Ukraine’s southwest.
After completing the capture of Luhansk province in late June, the Russian military declared what it called an operational pause to regroup and rearm. Independent analysts say Russia’s heavy casualties would force it to reconstitute units, and they stress that although Russia has cobbled together units, it will continue to face persistent manpower problems in the months ahead.
Russia has diverted about 10,000 paratroopers from the front north of Sloviansk to the southern Kherson region, said Serhiy Grabskyi, a retired Ukrainian colonel and commentator on the war for Ukrainian media.
Last week, Ukrainian soldiers advanced north of Sloviansk, claiming to liberate a village that had been fought over for months, Dovhenke. “They are frankly stuck in Donbas,” Mr. Grabskyi said of the Russians. “And now, they have a new headache: The south.”
In contrast to Russia’s retreat from Kyiv last winter, which Russian officials announced as a shift in focus to the Donbas region, the redeployment to the south has been gradual and undeclared.
The shift has also been large, analysts say. Russia has “substantially reinforced” the south and seemed to be establishing a large mobile reserve force, according to Michael Kofman, the director of Russian studies at C.N.A., a research institute in Arlington, Va.
“That may be because they’re unsure exactly as to Ukrainian plans but they anticipate some kind of offensive in the south,” he told the podcast “War on the Rocks,” on Monday. But he added that Russian forces were still testing lines in the east, putting pressure on Ukrainian forces in the northeast, and making at least a limited attack in the south. “So you see now a kind of much more active battlefield,” he said.
Regional leaders on Monday outlined the steady toll of that activity. Mayor Ihor Terekhov of Kharkiv, in the northeast, which Russians have bombarded steadily since failing to seize it early in the war, reported at least seven explosions early on Sunday and said shelling continued on Monday, killing one civilian and damaging several homes.
“There is definitely no military infrastructure in this peaceful and densely populated area,” he wrote on Telegram.
In the eastern province of Donetsk, part of the Donbas, the regional official Pavlo Kyrylenko wrote on Telegram that Russian forces had killed five civilians and injured 17 on Sunday.
In the Donbas, the Russian Army has narrowed its offensive at least for now to an assault on the city of Bakhmut and the towns of Pisky and Avdiivka, all of which are being hammered daily by artillery.
On a recent visit, Bakhmut seemed to be teetering. Explosions and the metallic whistles of incoming shells rang out every few minutes. The only people on the streets appeared to be drunk, poor or elderly, with nowhere to run.
With the enemy close and tensions high, some vigilantism emerged. Residents beat an apparently intoxicated man who had started a fire with a cigarette.
The deputy mayor, Oleksandr Marchenko, said in an interview that Russians were closing in from three sides about six miles outside town, pointing to smoke from burning villages nearby. An outdoor market was reduced to a tangle of twisted sheet metal from obliterated stalls. In one backyard, a body lay under a sheet beside a fresh shell crater.
The fighting in the countryside between the Donbas towns, in contrast, has been a war of small steps that Ukrainian forces say are mostly in their favor. Soldiers are still dying every day, but Russia’s once-punishing artillery barrages targeting front lines have petered out, compared to their earlier furious pace.
On a recent, sweltering summer morning, Sgt. Serhiy Tyshchenko walked a warren of trenches dug into a tree line, tracing his troops’ slow advance on a southern rim of the eastern front line.
The focal point of the war has moved elsewhere, he said. “Our position is not a priority for us or for them,” he said.
He advanced by sending troops crawling on their stomachs at night among the roots and leaves of acacia trees, along three parallel tree lines beside wheat fields. Each time, they dug new trenches, gradually pushing back the Russians.
When he reached the former Russian line, a panorama of garbage emerged: Water bottles, empty cans of fish, plastic bags and discarded ammunition boxes lay everywhere. Flies buzzed about.
“They don’t care” said Sergeant Tyshchenko, “because it’s not their country.”
Yurii Shyvala contributed reporting from Sloviansk and Bakhmut, Ukraine, Maria Varenikova from Kyiv, Ukraine, Emma Bubola from London, Anastasia Kuznietsova from Mantua, Italy, and Alan Yuhas from New York.