The Ukrainian military said on Thursday that its forces were pushing in two directions in southern Ukraine, aiming to rip through Moscow’s heavily fortified defensive lines, as President Vladimir V. Putin of Russia acknowledged a major uptick in fighting.
“We confirm that hostilities have intensified and in a significant way,” Mr. Putin said on the sidelines of a summit of African leaders in St. Petersburg, Russia. It was the Russian president’s first direct comments on what U.S. officials have described as the start of Ukraine’s main thrust of its counteroffensive in the Zaporizhzhia region, involving thousands of soldiers newly outfitted with Western arms.
But there were few clear signs of progress in a campaign that military analysts have said will be long and difficult. The Ukrainian military, which has sought to maintain operational secrecy, gave no confirmation that its counteroffensive had entered a new phase.
Earlier on Thursday, Russia launched blistering artillery and aerial bombardments across southern Ukraine, the Ukrainian military said, an apparent effort to repel the intensifying assault. Russian forces are focusing their “main efforts on preventing the further advance of Ukrainian troops,” the Ukrainian military’s general staff said.
It said that Ukrainian forces “continue to conduct an offensive operation in Melitopol and Berdiansk directions,” two cities along the Sea of Azov, which Ukraine hopes to reach to drive a wedge through Russian-occupied territory in southern and eastern Ukraine.
Privately, Ukrainian officials said that reserve units trained for the counteroffensive were not yet in use, and that the units already engaged were still trying to create breaches in Russia’s defenses.
Two American officials, who spoke on the condition of anonymity to discuss details of the campaign, said they believed that Ukraine’s “main thrust” was taking place in the direction of Robotyne, which is about six miles from the Ukrainian-controlled town of Orikhiv and about 50 miles north of Melitopol.
The Russian Defense Ministry said on Thursday that Ukraine’s assault in the area had failed, suffering “heavy losses,” and that Kyiv’s forces did not go on the attack overnight.
The United States’ defense secretary, Lloyd J. Austin III, speaking to reporters while visiting Papua New Guinea on Thursday, did not comment on the claims that the counteroffensive was in a new phase. He said that Kyiv had done a good job “preserving manpower and equipment” despite months of bloody fighting, and that it still had “a number of options available to them.”
Reaching Russian-occupied Melitopol is a key objective of the Ukrainian counteroffensive. Doing so would sever the so-called land bridge connecting Russian forces in eastern Ukraine from those in the south.
Ukraine’s three
major fronts
Main effort,
per U.S.
officials

Ukraine’s three
major fronts
Main effort,
per U.S.
officials
Ukraine is also trying to advance eastward in the direction of the city of Bakhmut and south toward Berdiansk, a port city about 70 miles east of Melitopol, a direction in which it reported progress.
Ukrainian Special Forces released video, verified by The New York Times, that appears to show Ukrainian soldiers taking Russian soldiers prisoner in the village of Staromaiorske. The village, about 90 miles north of Berdiansk, is near a cluster of farming hamlets along a winding river that Ukrainian forces claimed in the early days of their counteroffensive.
Earlier footage verified by The Times and posted to social media in recent days shows Ukraine’s southern advance into Russian-held territory, including Staromaiorske. One video, posted by a Ukrainian air reconnaissance team, shows soldiers, apparently Russian, fleeing near an intersection in the northwest part of the village. It was not clear from the footage how much control Ukraine has established there.
Carlotta Gall contributed reporting from the Zaporizhzhia region of Ukraine, and Haley Willis from Seoul.
