Ukrainian troops entered the key southern city of Kherson on Friday after Russia said it had withdrawn its troops.
Kherson had been occupied by Russian forces since March, but due to supply issues, the Kremlin said troops would withdraw from the west bank of the Dnipro River earlier this week.
On Friday, residents of the city welcomed Ukrainian forces back to the city in what was a huge blow to Vladimir Putin’s campaign.
What is the strategic importance of Kherson?
Kherson, which had a pre-war population of 280,000 fell into Moscow’s hands in the opening days of the war as Russian troops quickly pushed their attack north from the Crimean Peninsula — the region illegally annexed by the Kremlin in 2014.
The Kherson region was one of four where referendums were held by Russian forces, although these were widely discredited and not recognised by the West.
Not only is the city of the same name situated on the Dnipro River which bisects Ukraine, but it also lies near to the mouth of the Black Sea.
It also sits at a point where Ukraine can cut off fresh water from the Dnipro to Crimea.
Kyiv blocked those vital supplies after the Crimean Peninsula’s annexation, and President Putin mentioned the need to restore them as one reason behind his decision to invade Ukraine.
Capturing Kherson would also set the stage for reclaiming the Russia-occupied part of the Zaporizhzhia region and other areas in the south, and eventually pushing back into Crimea.
What is happening now?
In the last 24 hours, Ukrainian troops made gains north-west, west and north-east of the city of Kherson, advancing up to four miles in some areas as they re-entered the city, according to the Institute for the Study of War, a Washington-based think tank.
"Russians have moved to positions they hope will be easier to defend. Ukraine will have to decide whether, when, and how to keep pushing," said Olga Oliker, director for Europe and Central Asia at the International Crisis Group.
The arrival of Kyiv’s troops in the key city was confirmed by Ukraine’s defence intelligence agency, which said Kherson was now coming back under Ukrainian control. It also threatened to “destroy” any Russian soldiers who resisted.
“You have only one chance to avoid death - immediately surrender,” the Main Intelligence Directorate of the Defence Ministry said in the statement on the Telegram messaging app.
Despite withdrawing, it was reported that Russian forces had blown up a key bridge over the river to stop Ukrainian forces pursuing them as they retreated.
Ukrainian forces were “almost in full control” of Kherson on Friday afternoon according to Yuriy Sak, an adviser to Ukraine’s defence ministry.
Cheering crowds greeted Ukrainian troops as they arrived in the regional capital. Earlier, Ukrainian flags appeared in Kherson after Russia said it had completed the withdrawal of thousands of troops. Ukrainian forces are being cautious retaking the city for fear of booby traps or ambush.
What does the Kremlin say?
The Kremlin remained defiant Friday, insisting that battlefield developments in the Kherson region in no way represented an embarrassment for the Russian President.
Kremlin spokesman Dmitry Peskov told reporters the region’s status was "fixed" and that no changes were possible despite the Russian withdrawal.
"It is a subject of the Russian Federation - it is legally fixed and defined. There are no changes and there can be no changes," Mr Peskov said.
Fearing such a major Ukrainian counterattack, the Kremlin-installed regional administration in Kherson reportedly relocated at least 70,000 residents earlier this month.
What would losing Kherson mean for Russia?
A retreat from Kherson and other areas on the river’s west bank would shatter Russian hopes to press an offensive west to Mykolaiv and Odesa in order to cut off Ukraine’s access to the Black Sea.
Moscow had also hoped to build a land corridor to the separatist Transnistria region of Moldova, home to a major Russian military base.
"The loss of Kherson will turn all those southern dreams by the Kremlin into dust," said Ukrainian military analyst Oleh Zhdanov.
"Kherson is a key to the entire southern region, which would allow Ukraine to target key supply routes for the Russian forces. Russians will try to retain control of it using all means."
The loss of the city, the only regional capital to have been captured by Russian forces since its invasion in February, is widely seen by allies as a symbolically damaging defeat for Russia that is set to weaken Vladimir Putin and the morale of the Kremlin’s forces.
