Russia has shifted most of the focus of its war to eastern Ukraine, after a series of setbacks especially around the capital Kyiv. This push into the area known as Donbas could signal a more prolonged conflict, says the US.
What would Vladimir Putin need before he could claim his goal of “liberating” Ukraine’s old industrial heart and is that possible?
Russian forces have already triggered a humanitarian catastrophe in the east, reducing Mariupol to ruins, but they have failed to inflict defeat on Ukraine’s military. Warning of a new onslaught on the east, President Volodymyr Zelensky vowed: “We will fight for every metre of our land.”
Ukraine had already stationed its best-trained forces in the east because of an eight-year war with Russian-backed separatists. They are thought to have suffered heavy losses but are still a significant challenge to Russia’s invading army.
What is Ukraine’s Donbas?
When President Putin talks of Donbas, he is referring to Ukraine’s old coal and steel-producing area. But he really means the entirety of two big eastern regions, Luhansk and Donetsk, which run from outside Mariupol in the south all the way to the northern border.
“The key is that it has been identified by the Kremlin as a Russian-speaking part of Ukraine that is more Russia than Ukraine,” says Sam Cranny-Evans of the Royal United Services Institute.
These areas may be broadly Russian-speaking, but they are no longer pro-Russian. “Mariupol was one of the most pro-Russian cities in Ukraine and to level it is beyond my comprehension,” says defence specialist Konrad Muzyka, head of Rochan Consulting.
Last week, Russia claimed to have taken control of 93% of Luhansk region and 54% of Donetsk.
Russian forces are trying to encircle Ukraine’s army in the east. They have taken control of Izyum – a strategic town on the road between Ukraine’s second city Kharkiv and the separatist areas – and have bombarded a succession of Luhansk towns, including Rubizhne, Lysychansk, Popasna and Severodonetsk, destroying blocks of flats and killing civilians in their homes.
The towns that are now in Russian sights have already experienced years of war since 2014 and barely a day goes by now without a deadly attack.
Civilians are being moved out ahead of the Russian advance. Local leader Serhiy Haidai said 20 children were led to safety from the basement of a kindergarten in Lysychansk on Thursday and some 200 civilians climbed on to buses in Severodonetsk.
They were leaving for western Ukraine with nothing, said Mr Haidai, but they were alive.
Maryna Agafonova, 27, fled her family’s home in Lysychansk earlier this week. At the start of the war she said Russian forces had targeted the outskirts of the town but had lately hit the centre. “They attacked hospitals and residential buildings. There is no heating and no electricity. My parents are still there.”
Ukrainian forces were still holding out there in numbers, she told the BBC: “They don’t let the Russians occupy it.”
Russia’s next aim will be to push south to encircle Slovyansk, a city of 125,000 people that already experienced war at close hand when it was seized by Russian-backed forces in 2014 before being recaptured.
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Why Putin wants to control Donbas
The Russian leader has repeatedly made the unfounded accusation that Ukraine has carried out genocide in the east.
When the war began, two-thirds of the eastern regions were in Ukrainian hands. The rest was run by separatists, who created Russian-backed statelets during a war that began eight years ago.
If Russia were to conquer both big regions, then the next step could be to annexe them too, just like it did with Crimea in 2014.
Before invading Ukraine, President Putin recognised the entirety of the two eastern regions as independent of Ukraine. The Russian puppet leader in Luhansk has already spoken of a referendum in the “near future”, although the idea of even a sham vote taking place in a war zone seems absurd.
‘Scary’ existence in separatist Luhansk
Life under the control of Russian-backed separatists is quieter, although separatist authorities have accused Ukrainian forces of shelling residential buildings and killing civilians. Officials in the Donetsk statelet say 72 civilians have died since mid-February.
One woman in Luhansk told the BBC on condition of anonymity that she had seen a lot of Russian military armour in the city and the atmosphere now was one of fear and caution.
“I’m scared – it’s just scary,” she said. Men of military age were required to join the local militia so anyone who avoided the draft was in hiding, she explained.
“They’re mobilising [men] on the streets, catching them. There are no men in the shops, in town, on the streets.” As a result all male-dominated businesses are shut, she said.
“We’re already Russia, although just informally. Everyone has a Russian passport.”
Will Ukraine’s forces hold out?
At the start of the war, the 10 brigades that made up the Joint Forces Operation (JFO) in the east were regarded as the best-equipped and best-trained soldiers that Ukraine has.
“We don’t really know the strength of Ukrainian forces now,” said Sam Cranny-Evans of Rusi, who believes their numbers will have been boosted by volunteers in recent weeks.
Russian forces have already sustained high losses after more than five weeks of conflict and morale is thought to be low. They are made up of men enlisted from the local separatist areas as well as the broader Russian army.
However, they have seized a considerable part of the south-east and will hope to control the entire stretch of coastal territory from Crimea to the Russian border.
“The main goal for the Ukrainians is to incur as big losses on the Russian side as possible and the Ukrainians are using asymmetric tactics to avoid big battles,” says Konrad Muzyka.
One man called Mykyta who managed to flee the Russian bombardment of Mariupol said he was confident the Ukrainian army would succeed in fighting back.
“Some day they will return our cities, the Azov battalion will not surrender Mariupol,” he told the BBC. “The Ukrainian army is very cunning, I didn’t see them in my city, but I heard them, they are very good at disguise.”