Russia claimed control on Sunday over the last Ukrainian stronghold in an eastern province that is key to achieving a major goal of its invasion.

Ukraine’s general staff of the military reported that its forces had withdrawn from Lysychansk in Luhansk province, but the president said the fight for the city was ongoing.

If confirmed, Russia’s complete seizure of Luhansk would provide its forces a stronger base from which to press their advance in neighbouring Donetsk province and bring them one step closer to achieving one of President Vladimir Putin’s major goals: capturing the entire Donbas.

Russian defence minister Sergei Shoigu told President Vladimir Putin that Russia’s troops, with members of a local separatist militia, “have established full control over the city of Lysychansk” and now hold all of Luhansk, according to a ministry statement published on Sunday.

As is typical with such descriptions, the Russian statement characterised the victories as “the liberation of the Luhansk People’s Republic”.

Separatists in Luhansk and Donetsk, which have significant Russian-speaking populations, have declared independence from Kyiv.

Russia recognised their independence earlier this year ahead of its February 24 invasion of Ukraine.

Ukrainian and Russian forces have fought fiercely for Lysychansk in recent days after neighbouring Sievierodoentsk fell last week.

“We cannot give you the final judgment. Lysychansk is still being fought for,” Ukrainian president Volodymr Zelensky told a news conference on Sunday alongside Australia’s visiting prime minister.

He said Ukrainian forces were still battling Russia’s soldiers on the city’s outskirts and that territory can move quickly from one side to the other.

Oleksiy Arestovych, an adviser to Mr Zelensky, had predicted late on Saturday that Lysychansk’s fate could be determined within days.

The capture of Lysychansk would give the Russians more territory from which to intensify attacks on Donetsk in the Donbas, a region of mines and factories where Moscow-backed separatists have been fighting Ukrainian forces since 2014.

If Russia prevails in the Donbas, Ukraine would lose not only land but perhaps the bulk of its most capable military forces, opening the way for Moscow to grab more territory and strengthen its ability to dictate terms to Kyiv.

Already, Russian forces have concentrated rocket attacks on the sizable Ukrainian-held city of Slovyansk in Donetsk.

New attacks were reported in the city on Sunday. At least six people were killed, regional government spokeswoman Tatyana Ignatchenko told Ukrainian TV.

Kramatorsk, another major city in the Donetsk region, also came under fire, the regional administration said.

Far from the fighting in the east, Australian prime minister Anthony Albanese, on Sunday, visited a town near the capital that was severely damaged early in the war. Albanese called the destruction in Irpin “devastating”.

“These are homes and these are livelihoods and indeed lives that have been lost here in this town,” he said.

Elsewhere, the exiled mayor of the Russia-occupied city of Melitopol said on Sunday that Ukrainian rockets destroyed one of four Russian military bases in the city.

Attacks were also reported inside Russia, in a revival of sporadic apparent Ukrainian strikes across the border.

The governor of the Belgorod region in western Russia said fragments of an intercepted Ukrainian missile killed four people on Sunday.

In the Russian city of Kursk, two Ukrainian drones were shot down, according to the Russian defence ministry.

Kursk regional governor Roman Starovoit said the town of Tetkino, on the Ukraine border, came under mortar fire.