The war in the east, where Russia is focussing its attention, is now primarily an artillery battle.

In Sievierodonetsk, the small city that has become the focus of Russia's advance in eastern Ukraine and one of the bloodiest flashpoints in a war well into its fourth month, further heavy fighting was reported.

READ MORE

Fierce fighting in east Ukraine as Zelensky says world must not look away

Fire extinguisher flies away during unsuccessful attempt to douse car fire in Russia

The war in the east, where Russia is focussing its attention, is now primarily an artillery battle in which Kyiv is severely outgunned, Ukrainian officials say. That means the tide of events could be turned only if Washington and others fulfil promises to send more and better weaponry, including rocket systems.

"This is an artillery war now," Vadym Skibitsky, Ukraine's deputy head of military intelligence, told Britain's Guardian newspaper.

A Russian military convoy moves on a highway near Mariupol, Ukraine. File/AP

"Everything now depends on what (the West) gives us. Ukraine has one artillery piece to 10 to 15 Russian artillery pieces."

Germany, among the largest suppliers of weapons since Russia invaded but criticised for being slow to supply the heavy weaponry Kyiv says it needs, plans to revise its rules on arms exports to make it easier to arm democracies like Ukraine, Der Spiegel reported on Friday.

Cholera

To the south, the mayor of Mariupol — reduced to ruins by a Russian siege — said sanitation systems were broken and corpses were rotting in the streets.

"There is an outbreak of dysentery and cholera," Vadym Boichenko told national television. "The war which took over 20,000 residents ... unfortunately, with these infection outbreaks, will claim thousands more Mariupolites," he said, adding some wells had been contaminated by corpses.

The United Nations to establish a humanitarian corridor to allow residents.

Boichenko called on the United Nations and the International Committee of the Red Cross to establish a humanitarian corridor to allow remaining residents to leave the city, which is now under Russian control.

In a snapshot of the war's wider impact, the UN food agency said reduced exports of wheat and other food commodities from Ukraine and Russia could inflict chronic hunger on up to 19 million more people globally over the next year.

Russia is hoping to capture all of the eastern province of Luhansk, which it demands Ukraine cede to separatists along with neighbouring Donetsk. The two provinces make up the Donbas region, where Moscow has backed a revolt by separatist proxies since 2014.

To that end, the Kremlin has concentrated its forces into a battle for Sievierodonetsk, which is in Luhansk.

Ukrainian troops have largely pulled out of the city's residential areas but have not yielded their foothold on the east bank of the Siverskiy Donets River. Russian forces are also pushing from the north and south to try to encircle the Ukrainians, but have made limited progress.

Reuters