Ukraine’s President Volodymyr Zelensky stated in a video message published Monday that Russia’s military aggression is reducing the Ukrainian port city of Mariupol to ashes, but that the city would “survive.”

Mariupol, which had a population of roughly 450,000 people before the war, has been under near-constant shelling from Russian forces since early March, with satellite photos indicating severe damage to residential areas.

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Josep Borrell, the European Union’s foreign policy leader, stated on Monday that “what’s happening Mariupol is a massive war crime.”

In his speech, Zelensky urged Ukrainians to “do everything you can to defend our country, to save our people.”

Since the Russian invasion of Ukraine began in late February, “we are seeing more and more [Ukrainian] heroes. Once ordinary Ukrainians, and now true fighters,” he remarked.

The Ukrainian leader further stated that regular Ukrainians are “rising” to the point where Russia “doesn’t believe that this is the reality,” adding, “we will make Russia believe.”

“Fight, fight, fight, and help,” he exhorted the Ukrainians.

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Mariupol is only a speck on the map, but it now stands obstinately in the way of Russian forces who have burst out of the Crimean peninsula.

They are pushing north-east in an attempt to connect with their comrades and Ukrainian-separatist allies in eastern Ukraine’s Donbas region.

If Mariupol is taken, Russia will have complete control of more than 80 percent of Ukraine’s Black Sea coastline, cutting off its maritime trade and further isolating it from the rest of the world.

Mariupol has long been a strategically important port on the Black Sea’s Sea of Azov.

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It is the largest port in the Azov Sea region, with deep berths, and is home to a significant iron and steel industry. Mariupol is an important export hub for Ukrainian steel, coal, and corn to consumers in the Middle East and beyond in normal times.

Mariupol is home to the Azov Brigade, a Ukrainian militia force named after the Sea of Azov, which connects Mariupol to the remainder of the Black Sea. The Azov Brigade includes far-right extremists such as neo-Nazis.

Despite constituting only a small proportion of Ukraine’s combat troops, this has served as a valuable propaganda tool for Moscow, providing a pretext for informing Russia’s populace that the young men sent to fight in Ukraine are there to free their neighbour of neo-Nazis.

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If Russia captures Mariupol, it will be psychologically crucial for both sides in this battle.

A Russian triumph in Mariupol would allow the Kremlin to demonstrate to its people, via state-controlled media, that Russia was achieving its goals and making progress.

There is a historical significance to all of this for President Putin, who looks to be taking this battle personally. He considers Ukraine’s Black Sea coastline to be part of Novorossiya (New Russia), a Russian empire dating back to the 18th century.