Russian forces bombarded front-line Ukrainian troops and towns in the eastern Donetsk region on Tuesday in what appeared to be early salvoes of a new offensive, as Western allies met to weigh sending more arms to Kyiv for an expected counter-attack.
Much of Russia's artillery fire was focused on Bakhmut, a bombed-out city in Donetsk province and a principal target for President Vladimir Putin. Ukrainian troops there have fortified positions in anticipation of street fighting.
"There is not a single square metre in Bakhmut that is safe or that is not in range of enemy fire or drones," regional governor Pavlo Kyrylenko told Ukraine's national broadcaster.
He said Russian guns were pounding targets all along the front lines in Donetsk, which along with Luhansk province makes up the Donbas, Ukraine's industrial heartland and a major Russian objective.
Bakhmut's capture would provide a stepping stone for Russia to advance on two bigger Donetsk cities, Kramatorsk and Sloviansk, and give Moscow new momentum after months of battlefield setbacks following its invasion last February.
White House spokesperson John Kirby said in Washington that Russian forces had made incremental progress in their assault on Bahkmut but it remained unclear whether the city would fall.
With the first anniversary of Russia's invasion nearing, the Kremlin has intensified operations across a broad swathe of southern and eastern Ukraine, and a major new offensive has been widely anticipated.
U.S. Defense Secretary Lloyd Austin said he expected Ukraine to launch its own offensive against Russia in the spring and Kyiv's allies were working to ensure they had the armour, firepower and logistics to make it effective.
"Ukraine has urgent requirements to help it meet this crucial moment in the course of the war. We believe there'll be a window of opportunity for them to exercise initiative," Austin told a meeting of defence ministers of NATO and other allies of Ukraine to discuss options for more military aid.
"The Kremlin is still betting it can wait us out, but one year on we are as united as ever. That shared resolve will help sustain Ukraine's momentum in the crucial weeks ahead."
Ukraine is currently using shells faster than the West can make them.
MORE MILITARY AID?
Promised battle tanks last month, Ukraine is also desperate for fighter jets and longer-range missiles soon to nip any significant new Russian offensive in the bud and help turn the tide against Moscow's far superior firepower.
Before the gathering, NATO Secretary-General Jens Stoltenberg said there were no signs Putin was preparing for peace. "What we see is the opposite, he is preparing for more war, for new offensives and new attacks," he told reporters.
The Kremlin, which calls the invasion a "special military operation" to eliminate security threats, said NATO was demonstrating its hostility towards Russia every day and was becoming more and more involved in the conflict.
Kyiv and its allies call Russia's actions an unprovoked land grab.
Ukraine's military said on Tuesday its forces had repelled attacks in five settlements in Luhansk and six in Donetsk, including around Bakhmut, over the past 24 hours. They had also beaten back an attack on a town in the Kharkiv region, which borders Russia in northeast Ukraine, it said.
Britain said on Tuesday mercenaries from the Wagner group, who have spearheaded the Russian assault on Bakhmut, had made small gains in its northern outskirts in the past three days.
A regional road and rail transport and logistics hub, Bakhmut has endured months of shelling and many districts are in ruins. Only about 5,000 civilians are left there out of a pre-war population of about 70,000, Governor Kyrylenko said.
The acting head of the Russian-installed administration in Donetsk, Denis Pushilin, said Ukrainian troops were entrenched in Bakhmut but Russian forces were making headway.
Wagner head Yevgeniy Prigozhin said Russian forces would not be able to capture the town anytime soon. In a post on the Telegram channel, Prigozhin said Ukraine was reinforcing with up to 500 new fighters a day.
""The heaviest battles are taking place to the north (of Bakhmut). There are no grounds for encircling the enemy in the northern areas," he said.
WAITING FOR BIG PUSH
Ukrainian officials also said the Russians had suffered big losses around Vuhledar, a town 150 km (90 miles) southwest of Bakhmut, including tanks, armoured vehicles and personnel.
Reuters was not able to independently verify battlefield reports.
On the snowbound Ukrainian front line between Vuhledar and Marinka 30 km to the northeast, and 400 metres (1,300 feet) from Russian positions, two officers said Kyiv's forces were holding firm against intensifying Russian artillery and mortar fire.
"Previously there were a couple of artillery and mortar attacks a day, now there are more than 10 a day. Artillery is working harder than the enemy's infantry," one officer who identified himself just as "Deputy" told a Reuters news team.
Russia now holds swathes of the southern regions of Kherson and Zaporizhzhia, including its nuclear plant, nearly all of Luhansk and over half of Donetsk, including the regional capital. Despite not fully controlling any of the four regions, Moscow claims to have annexed them all.
Kyiv-based military analyst Oleksandr Musienko told Reuters the Russian push around Bakhmut, Vuhledar and Adviivka could signal the beginning of the big offensive. Fighting had also intensified in Zaporizhzhia and Kharkiv, he said.
"Russia wants to do this in order to stretch our forces, but that means that Russia does not learn from its mistakes because experience has shown that stretching of forces like that in 2022 did not bring them any significant victories," he said.
(Reporting by Caleb Davis, Sabine Siebold, Pavel Polityuk, Ron Popeski, Lydia Kelly, Aleksandar Vasovic, Tassilo Hummel, Steve Holland and Doina Chiacu; writing by Angus MacSwan and Mark Heinrich; editing by Robert Birsel, Andrew Cawthorne and John Stonestreet)