After Western military agencies reported that Moscow's offensive in the Donbas region had halted, Ukraine counterattacked Russian soldiers on the eastern front on Monday, with fighting reported near the country's second-largest city of Kharkiv.

In televised remarks, the adviser to the Ukrainian interior minister, Vadym Denisenko, described the battle near Kharkiv as "our counter-offensive."

"It is no longer possible to stop... This allows us to move to the rear of the Russian force group "he continued.

The governor of the Donbas region of Luhansk, Serhiy Gaidai, stated that the situation "remains difficult" as Russian soldiers attempt to seize the city of Sieverodonetsk.

He stated that the Lugansk People's Republic leaders, the part of Luhansk controlled by separatists backed by Russia, had declared a general mobilization, adding, "either fight or get shot, there is no other choice."

In the south, fighting was raging near the city of Kherson, and Russian missiles were special residential districts of Mykolayiv, according to the presidential administration in Kyiv.

The reports were unable to be verified by Reuters.

On Sunday, NATO Secretary-General Jens Stoltenberg announced that Russia's offensive in Donbas has halted and that Ukraine may win the war, which few military analysts anticipated when Russia invaded Ukraine on February 24.

Since then, Russian troops have suffered massive casualties while reducing cities and towns to rubble, murdering thousands, and forcing over six million people to escape to neighboring nations. Russia denies civilian targeting.

Finland said on Sunday that it would apply to join the Atlantic military alliance, dealing a strategic blow to Russia, which has resisted NATO expansion for decades.

The ruling Social Democrats in Sweden supported NATO membership, clearing the path for an application and ending decades of military neutrality.

NATO and the United States expressed confidence that both nations would be welcomed into the alliance and that Turkey's objections could be resolved. Turkey wants the Nordic countries to cease supporting Kurdish militant groups on their soil.

Since February, Ukraine has achieved several victories, including reversing a Russian push on Kyiv and the expulsion of Russian forces from Kharkiv.

Since mid-April, Russian forces have focused most of their firepower on capturing the Donbas, two eastern provinces.

Days before its invasion, Moscow recognized the independence of the self-proclaimed Donetsk People's Republic and the Lugansk People's Republic in the Donbas.

According to British military intelligence, Russia lost almost one-third of the ground combat force it sent in February, and their attack in Donbas was "significantly behind schedule."

Moscow describes its invasion of Ukraine as a "special military operation" to clear the country of Nazis, a claim Kyiv and its Western allies deem to be a bogus justification for an unprovoked attack.

Fighting around Izium

Ukrainian troops' morale was boosted by the country's victory in the Eurovision music contest over the weekend, with some predicting future battlefield successes.

Vitaliy, a soldier, encamped north of Kyiv, remarked, "We have shown that we can not only fight, but we can also sing very nice,"

The heaviest fighting looked to be occurring around the eastern Russian-held city of Izium, where Russia claimed to have fired missiles toward Ukrainian forces.

The Joint Forces Task Force of Ukraine reported that its troops had repelled 17 attacks and destroyed 11 pieces of Russian equipment on Sunday. According to the Ukrainian air force command, Ukrainian forces shot down two helicopters, two cruise missiles, and seven drones.

The task force noted that Russia continues to attack civilian areas along the entire front line in the Luhansk and Donetsk provinces by firing on 23 villages and towns.

The Ukrainian military recognized setbacks and reported that Russian forces "continue to advance" in several Donbas regions.

According to the Ukrainian military, the Russian bombing of steelworks in the southern port of Mariupol, where a few hundred Ukrainian fighters are still holding out weeks after the city came into Russian hands, continued unabated on Sunday.

In a video posted by a pro-Russian rebel commander, blazing projectiles were seen raining down on the steelworks.

On Monday, Alexander Khodakovsky, a Donetsk commander, reported on his Telegram channel that ten Ukrainian fighters carrying white flags came from a tunnel in the Azovstal complex. Reuters could not verify the report.

Volodymyr Zelensky, the president of Ukraine, stated that "very difficult and delicate negotiations" were taking place to preserve Ukrainians in Mariupol and Azovstal.

Natalya, a resident of Mariupol, reported that her flat had been bombed and three neighbors had been slain.

"We were unable to bury them due to the shelling. Each day, we were burying a person in a cemetery that could not be covered with dirt due to bombardment "She stated,