Odesa, which Ukraine fears could be the next target of Russia’s offensive in the south, is the country’s main port and is vital for its economy.

But the city of one million people close to the Romanian and Moldovan borders also holds a special place in the Russian imagination.

A cosmopolitan port on the Black Sea with stunning 19th-century architecture, sandy beaches and a Mediterranean climate, it has a Russian-speaking majority.

Ukrainian President Volodymyr Zelenskyy warned on Sunday that Moscow was “preparing to bomb Odesa”, saying, “It will be a war crime … a historical crime.”

French President Emmanuel Macron told Russian President Vladimir Putin during a phone call on Sunday of his concerns about a possible imminent attack on the Ukrainian city of Odesa, according to a statement from Macron’s office.

Odesa is Ukraine’s main port complex. The one in the city itself handles petrol and metals, while others in nearby Youjni and Illytchyivsk handle chemicals and containers.

A large part of Ukraine’s enormous corn and barley exports pass through the ports.

The city’s beaches, Italianate architecture and relaxed way of life have made it a tourist magnet, with numbers increasing since Russia annexed Crimea in 2014.

Odesa is located some 70 kilometres (43 miles) from Transnistria, the tiny unrecognised separatist Russian-speaking statelet that broke away from Moldova as the Soviet Union collapsed. NATO member Romania is a four-hour drive away.

But the city resisted the separatist push that took parts of the mainly Russian-speaking Donbas region in the east out of Kyiv’s control after Putin annexed Crimea.