Ukraine's interior minister has today said there was no imminent risk of Russians marching on Kyiv, but the capital would not let its guard down.
"There is no danger of an attack on Kyiv today," Interior Minister Denys Monastyrsky said.
"There is no concentration of troops near the Belarusian border, but we understand that any scenarios are possible tomorrow," he added.
"Therefore, serious training is under way - preparation of the line of defence, training of troops who will remain" in Kyiv and around the city.
The minister also said Russian air strikes could hit at any time.
"Any place in Ukraine can be a target for rocket fire, including Kyiv," he said.
Targets could even include "the government quarter" and "historic centre" of the capital, he added.
Russian forces had their sights set on Kyiv when they moved into Ukraine in late February, rapidly taking over control of several towns around the city.
But the invading forces withdrew from those suburbs a month later.
Meanwhile, Ukrainian forces claimed to have pushed forward in intense street fighting in the eastern city of Sievierodonetsk.
But they also said more artillery was needed to offset Russia's massive firepower.
The regional governor of Luhansk in the eastern Donbas region said Western artillery would quickly help secure a Ukrainian victory for the bombarded city.
"As soon as we have long-range artillery to be able to conduct duels with Russian artillery, our special forces can clean up the city in two to three days," governor Sergiy Gaiday said.
In the south, Ukraine's defence ministry said it had captured new ground in a counter-attack in Kherson province, targeting the biggest swathe of territory Russia has seized since its invasion in February.
We need your consent to load this rte-player contentWe use rte-player to manage extra content that can set cookies on your device and collect data about your activity. Please review their details and accept them to load the content.Manage Preferences
The battle amid the ruins of Sievierodonetsk, a small industrial city, has become one of the war's bloodiest, with Russia concentrating its invasion force there.
Both sides say they have inflicted massive casualties.
Sievierodonetsk and its twin city Lysychansk on the opposite bank of the Siverskyi Donets river are the last Ukrainian-controlled parts of Luhansk province, which Moscow is determined to seize as one of its principal war objectives.
Russian forces are focusing all of their might in the area, Ukraine's Security Council Secretary Oleksiy Danilov told Reuters today.
"They don't spare their people, they're just sending men like cannon fodder," he said. "They are shelling our military day and night."
Two Britons and a Moroccan who were captured while fighting for Ukraine were sentenced to death by a court in the self-proclaimed Donetsk People's Republic (DPR), one of Russia's proxies in eastern Ukraine, Russian news agencies reported.
In a rare update from Sievierodonetsk, the commander of Ukraine's Svoboda National Guard Battalion, Petro Kusyk, said Ukrainians were drawing the Russians into street fighting to neutralise Russia's artillery advantage.
"Yesterday was successful for us - we launched a counteroffensive and in some areas we managed to push them back one or two blocks. In others they pushed us back, but just by abuilding or two," he said in a televised interview.
"Yesterday the occupiers suffered serious losses - if everyday were like yesterday, this would all be over soon."
But he said his forces were suffering from a "catastrophic" lack of counter-battery artillery to fire back at Russia's guns - and getting such weapons would transform the battlefield.
"Even without these systems, we are holding on fine. There is an order to hold our positions and we are holding them. It is unbelievable what the surgeons are doing without the proper equipment to save soldiers' lives."
Sievierodonetsk Mayor Oleksandr Stryuk said around 10,000 civilians were still trapped inside the city -around a tenth of its pre-war population.
In Soledar, a salt-mining town near Bakhmut close to the front line, buildings had been blasted into craters.
Remaining residents, mostly elderly, were sheltering in a crowded cellar.
Antonina, 65, had ventured out to see her garden. "We are staying. We live here. We were born here," she sobbed. "When is it all going to end?"
In the south, Moscow is trying to impose its rule on a tract of occupied territory spanning Kherson and Zaporizhzhiaprovinces, where Russian-installed proxy authorities say they are planning referendums to join Russia.
Thousands of people have been killed and millions have fled since Moscow launched its "special military operation" to disarm and "denazify" its neighbour on 24 February.
Ukraine and its allies call the invasion an unprovoked war of aggression.
Ukraine is one of the world's biggest grain and food oil exporters, and international attention has focused in recent weeks on the threat of international famine seen as caused by Russia's blockade of Ukraine's Black Sea ports.
"Millions of people may starve if the Russian blockade of the Black Sea continues," Ukrainian President Volodymyr Zelensky said in televised remarks today.
Moscow blames the food crisis on Western sanctions restricting its own grain exports. It says it is willing to let Ukrainian ports open for exports if Ukraine removes mines and meets other conditions.
Kyiv calls such offers empty promises.