Ukrainian forces are piling pressure on Russian troops in the southern region of Kherson that Moscow occupied at the start of its invasion of Ukraine on February 24 Losing control of the region would be another big setback for President Vladimir Putin.
Here is why the region is strategically important for the course of Russia's war in Ukraine.
Gateway to Crimea
Kherson region borders Crimea and provides Moscow with a land bridge to the Black Sea peninsula that it seized from Kyiv in 2014. Ukraine retaking swathes of the Kherson region would deprive Moscow of that land corridor.
It would also bring long-range Ukrainian artillery closer to Crimea, which Moscow sees as vitally important to its interests.
The Ukrainian peninsula, whose annexation Putin sees as a key achievement of his more than two decades in power, is home to a huge Russian military force and the Black Sea Fleet, which Moscow uses to project power into the Mediterranean and the Middle East.
Fresh water supplies
Fresh water supply to Crimea would also be imperiled if Ukraine retakes the Kherson region.
After Moscow seized Crimea, Kyiv blocked water supplies via a canal from the Dnipro River. When Russia seized chunks of the Kherson region and neighboring Zaporizhzhia region to the east, it immediately moved to unblock the canal to return freshwater flow. Russia needs that water for the local population, the irrigation of the peninsula's arid land and for numerous military facilities.
Logistics routes
Russian forces are dug in on the right-western-bank of the Dnipro River north of the Kherson region. It is the only place where Russia has a presence on the right bank of the vast river that bisects Ukraine.
Ukrainian forces have been hammering the bridges over the river to hurt Moscow's ability to resupply. Losing that side of the river would allow Ukraine to attack Russian supply lines supporting the Zaporizhzhia region and seek to recapture its Zaporizhzhia nuclear power plant, military analysts say.
"The right bank is important for both sides - for (Russia) in order to ensure the steadiness of the defense of the Zaporizhzhia direction, and for (Ukraine) to free this direction and cut off these three important arteries: the land corridor to Crimea, the water to Crimea and to return control of the (nuclear plant)," said Oleh Zhdanov, a military analyst.
Symbolyc significance
The city of Kherson is to date the only regional capital that Russian forces have captured since the February 24 invasion. Losing it would therefore be a major symbolic blow to the Kremlin and indicate Russia had - for now - failed to press ahead to the cities of Mykolaiv and Odesa whose capture Moscow has sought, said Oleksander Musiyenko, a military analyst.
"It's clear the loss of Kherson and the Kherson bridgehead will have consequences for Russia's image and will be viewed negatively inside Russia," he said.
"It's clear the loss of Kherson and the Kherson bridgehead will have consequences for Russia's image and will be viewed negatively inside Russia."
Oleksander Musiyenko
Black Sea control
The Kherson region, which had a pre-war population of more than 1 million, lies on the Black Sea. Recapturing it would help Kyiv wrest back control of some of the coastline to a sea that is a critical artery for its food exports to foreign markets.