Russia on Tuesday reported its forces had taken full control of residential neighbourhoods in Ukraine's flashpoint city of Severodonetsk, after Kyiv said its troops were fighting on in the eastern hub despite being outnumbered.

"The residential areas of the city of Severodonetsk have been fully liberated," Russian Defence Minister Sergei Shoigu told a defence ministry meeting.

The Russian army was still seeking to establish control over the city's "industrial zone and the nearest settlements", he added, amid conflicting reports of who is in control of what.

A plant for repairing freight cars was hit by airstrikes in the southeast of Kyiv
A plant for repairing freight cars was hit by airstrikes in the southeast of Kyiv AFP / Genya SAVILOV

Moscow has been pushing for control of the strategic industrial hub as part of its bid to conquer a vast swathe of eastern Ukraine but Kyiv's forces have so far managed to hold out,

"Our heroes are holding their positions in Severodonetsk. Fierce street fights continue in the city," Ukrainian President Volodymyr Zelensky said in a video address late Monday.

Zelensky warned Ukrainian forces in the key city were outnumbered and the Russians "are stronger". He was speaking to journalists after visiting frontline positions in Lysychansk, across the river from Severodonetsk.

Thousands of civilians have been killed and millions forced to flee their homes since President Vladimir Putin ordered Russian troops into Ukraine on February 24.

President Volodymyr Zelensky (centre) 'got himself acquainted with the operational situation on the front line of defence', the presidency said
President Volodymyr Zelensky (centre) 'got himself acquainted with the operational situation on the front line of defence', the presidency said UKRAINIAN PRESIDENTIAL PRESS SERVICE via AFP / Handout

After being repelled from other parts of the country, including Kyiv, Russia has concentrated its assault on the eastern Donbas region and had been making slow but steady progress.

Severodonetsk -- the largest city still in Ukrainian hands in the Lugansk region of the Donbas -- has been the focal point in recent weeks.

Sunday brought the first Russian missile strikes on Kyiv since April 28
Sunday brought the first Russian missile strikes on Kyiv since April 28 AFP / Sergei SUPINSKY

The leader of Ukraine's pro-Russian separatists in Donetsk, Denis Pushilin, on Tuesday confirmed the death of another Russian general in the fighting.

Pushilin expressed on Telegram his "sincere condolences to the family and friends" of Major General Roman Kutuzov, "who showed by example how to serve the fatherland".

Ukraine's forces have claimed to have killed several of Russia's top brass but their exact number is not known as Moscow is tight-lipped on losses.

Latest developments in Russia's war with Ukraine, with photos
Latest developments in Russia's war with Ukraine, with photos AFP / Sabrina BLANCHARD

Defence Minister Shoigu said Russia had completed demining of the eastern port city of Mariupol, the second busiest in Ukraine before the conflict.

"It is operating as normal and has accepted the first cargo ships," Shoigu said.

With fighting raging in the east of Ukraine, Kyiv hit out at the UN's nuclear watchdog for trying to visit Europe's largest nuclear reactor in the south of the country while it is under Russian occupation.

Russian Foreign Minister Sergei Lavrov's plans to visit Serbia were blocked when several European countries refused him overflight rights.
Russian Foreign Minister Sergei Lavrov's plans to visit Serbia were blocked when several European countries refused him overflight rights. RUSSIAN FOREIGN MINISTRY via AFP / Handout

The head of the International Atomic Energy Agency (IAEA), Rafael Grossi, said on Monday his agency was preparing an expert mission to the Zaporizhzhia nuclear plant.

Grossi said on Twitter the visit was arranged after Ukraine had "requested" it.

But Ukraine's nuclear agency, Energoatom on Tuesday accused Grossi of lying and said it did not greenlight the trip.

"The visit to the plant will only become possible when Ukraine takes back control of the site," Energoatom wrote on Telegram.

"We consider this declaration a new attempt to gain access to the Zaporizhzhia power plant to legitimise the presence of the occupiers and approve their actions."

In 2021 -- well before Russia's invasion of Ukraine -- the plant represented 20 percent of Ukraine's annual electricity production and nearly half of all nuclear power produced in Ukraine.

The Russian invasion, combined with supply chain snarls and climate change, has triggered stark warnings of global food shortages.

Moscow has blockaded the key black sea port of Odessa, and Zelensky said Ukraine had up to 25 million tonnes of grain that could not be exported.

"In the autumn that could be 70 to 75 million tonnes," said the president, whose country was the world's fourth biggest grain exporter before the war.

In Washington, US Secretary of State Antony Blinken said that reports Russia had stolen grain from Ukraine for export are "credible".

At a meeting of the UN Security Council, the United States and Europe urged Russia to stop alleged sexual violence by its army and proxies in Ukraine, allegations that Moscow denounced as "lies".

With the West seeking to tighten sanction screws on Russian oligarchs, the US Justice Department on Tuesday ordered the seizure of two aircraft owned by former Chelsea Football Club owner Roman Abramovich.

And in Fiji, a court ruled a $300-million superyacht linked by the US to sanctioned Russian oligarch Suleiman Kerimov could be handed over to US authorities.

The Amadea, which boasts a helipad, pool, jacuzzi and "winter garden", was impounded in Fiji in April at Washington's request.