Where is Donbas? Ukraine region map, Battle of Donbas explained - why do Russia and Putin want to capture it?
Donbas - or Donbass - contains the so-called Donetsk People’s Republic and the Luhansk People’s Republic
It said the “special military operation” would now focus on the “main goal, liberation of Donbas”, which borders Russia in the east of Ukraine.
“Now we can already state that the Russian troops have begun the battle for the Donbas, for which they have been preparing for a long time,” Zelensky said.
Russian forces attacked along a broad front in eastern Ukraine on Tuesday (19 April), as part of a full-scale ground offensive to take control of the country’s eastern industrial heartland in what Ukrainian officials called a “new phase of the war”.
Here is everything you need to know about it.
Where is Donbas?
The Donbas region is a mostly Russian-speaking industrial heartland in Ukraine’s east which borders Russia.
Ukraine’s General Staff said Russian forces are focusing their efforts on taking full control of the Donbas region.
It is important to Russia’s current vision for Ukraine, as it contains areas controlled by Russian-backed separatist groups, including the so-called Donetsk People's Republic and the Luhansk People's Republic, officially recognised by Putin ahead of his invasion.
Due to its proximity to Russia, Donbas is perhaps the area of Ukraine in which pro-Russian or anti-Ukrainian sentiment is strongest, and Moscow-backed separatists have been fighting Ukrainian forces for the past eight years in the region.
Pro-Russian and anti-government unrest first took hold of the region in 2014, following the Revolution of Dignity, which eventually lea to the annexation of Crimea by Russia.
The self-proclaimed republics held referendums on the status of Donetsk and Luhansk in May 2014.
The referendums, viewed as illegal by Ukraine and undemocratic by the international community, showed that about 90% of the population were in favour of independence from Ukraine.
However, similar referendums held today may have vastly different results, following Russia’s offensive on Ukraine.
Before Russia’s full-scale invasion, Donbas was split between Ukrainian-held territory, constituting about two-thirds of the region, and Russian-held territory, constituting about one-third.
Upon launching his invasion, Putin said it was partly intended to "protect" the people of the Donbas from the "abuse" and "genocide" of the Ukrainian government, though here is no evidence to support these claims.
Is Mariupol part of Donbas?
Mariupol, the contested city that has been left decimated by Russian forces, is part of Donbas, located towards the region’s southern extremities by the Azov coast.
The General Staff said the Russian military has continued to blockade and shell the strategic port city of Mariupol and fire missiles at other cities.
Denys Prokopenko, commander of the Azov Regiment of the Ukrainian National Guard, said in a video message that Russia had begun dropping bunker-buster bombs on the Azovstal steel plant where the regiment was holding out.
The sprawling plant contains a warren of tunnels where both fighters and civilians are sheltering. It is believed to be the last major pocket of resistance in the shattered city.
If Russia takes Mariupol, it would free up troops for use elsewhere in the Donbas, deprive Ukraine of a vital port, and complete a land bridge between Russia and the Crimean Peninsula, seized from Ukraine in 2014.
Other cities located within the Donbas region include Luhansk, Makiivka, Horlivka, Kramatorsk, Sloviansk, Alchevsk, Sievierodonetsk, and Lysychansk.
The city of Kramatorsk is the interim administrative centre of the Donetsk Oblast, whereas the interim centre of Luhansk Oblast is Sievierodonetsk.
How has Russia attacked?
Stepped-up assaults on the Donbas began on Monday (18 April) along a front of more than 300 miles, focused on the regions of Donetsk and Luhansk, with the Russian forces trying to advance in several sections, including from the neighbouring Kharkiv region.
In a video address, he said that a “significant part of the entire Russian army is now concentrated on this offensive.
“No matter how many Russian troops are driven there, we will fight,” Zelensky vowed. “We will defend ourselves.”
Troops battled in the streets of Kreminna on Monday before Russia was able to gain control of the city, according to Serhiy Haidai, Luhansk regional military administrator.
Haidai said that before advancing, Russian forces “just started levelling everything to the ground”. He said his forces retreated to regroup and keep fighting.
The breakthrough at Kreminna brings the Russians closer to the city of Slovyansk, which is seen as a key target in the Russian offensive. Slovyansk was seized by pro-Russian fighters in 2014, only to be retaken by Ukrainian forces months later following intense fighting.
Russian troops have already seized the city of Izyum, which sits north of Slovyansk, and they are poised to push toward the city from the north and the east.
Slovyansk lies just north of another key city, Kramatorsk, where an earlier Russian attack on a train station killed more than 50 people.
On Monday morning, Oleksiy Danilov, secretary of Ukraine’s national security council, told Ukrainian media that the defensive line had not been broken elsewhere.
“Fortunately, our military is holding out,” Danilov said.
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