By Marc Santora

KYIV – Ukrainian soldiers went on the offensive against Russian forces in northeastern Ukraine on Friday (6), seeking to drive them back from outside two key cities, as the gruelling battle for control over territory in the east increasingly turns into a brutal war of attrition, with neither side able to score a major breakthrough in the fighting.

Ukrainian officials are bracing for what they fear could be even more intense Russian assaults over the weekend, as President Vladimir Putin of Russia seeks to claim a victory that he can showcase Monday (9), Russia’s Victory Day holiday, an annual celebration of the Soviet defeat of Nazi Germany. Local leaders announced new curfews and issued urgent warnings about the threat of stepped-up Russian missile strikes.

Assessing the successes claimed by the two sides is difficult, with one taking a few villages one day in one area, only to lose just as many along a different part of the 300-mile-long front. But Ukraine’s assertion that it was shifting to offensive actions in part of the country came as more sophisticated weapons and long-range artillery provided by Western allies were flowing to the front, allowing Ukraine to take more aggressive action.

“There are fierce battles going on, as well as the transition from defensive operations to offensive actions in the Kharkiv and Izyum areas,” the Ukrainian commander in chief, Valeriy Zaluzhnyi, said he told Gen. Mark Milley, chairman of the US Joint Chiefs of Staff, on Thursday (5).

At the same time, Russian forces appear to have escalated their attempts to trap and destroy Ukrainian units farther south, in and around the cities of Kramatorsk and Sloviansk and the towns of Lyman and Barvinkove.

In the ruined city of Mariupol, where fighting continued to rage, an evacuation convoy was dispatched again Friday to the Azovstal steel plant, where about 200 civilians are still believed to be trapped underground, along with the last Ukrainian soldiers defending the city. Russian bombardment of the factory continued overnight, as Ukrainian fighters reported bloody close-quarter battles in a labyrinth of tunnels and nuclear fallout shelters, in what could prove to be the final battle in one of the war’s most savage campaigns.

Here are other major developments:

— US officials told The New York Times that US intelligence helped Ukrainian forces find and strike the flagship of Russia’s Black Sea fleet in April.

— The top UN rights official told a meeting of the UN Security Council on Thursday that scores of cases had been documented in which Russian forces targeted civilian Ukrainian men.

— Jill Biden, the first lady, arrived in Romania on Friday, kicking off her trip to Eastern Europe, where she will visit with refugees displaced by the war and tour the Slovakian border with Ukraine, according to her office.

— Chancellor Olaf Scholz of Germany said Thursday that the German foreign minister would visit Ukraine, a sign that weeks of diplomatic bickering between the two countries may have subsided.

-New York Times