Kyiv: Russian troops have seized the strategically important city of Kherson in Ukraine, The New York Times reported citing Ukrainian officials as saying.

"The city is surrounded," Kherson mayor Igor Kolykhaev said, according to The Kyiv independent, a Ukraine media outlet.

Kolykhaev said that the situation in the southern regional capital is "tense with Russian troops entering the city and taking administrative buildings", The Kyiv independent reported.

The fall of Kherson -- a city of 300,000 people, northwest of the Crimean peninsula -- is significant because it would allow the Russians to control more of Ukraine's southern coastline and to push west toward the city of Odessa, The NYT reported.

As the bombing of civilian targets in Ukraine intensified on Wednesday, reports of civilian casualties escalated.

The United Nations said that 227 civilians had been killed, but noted that number was likely an undercount.

As per the NYT report, the Ukrainian government initially put the number of civilian deaths at more than 2,000, but Ukraine's emergency services agency later called that figure "approximate," and said: "It is unknown how many people are actually still under fire and debris. There is no exact figure."

Russian forces launched military operations in Ukraine on February 24, three days after Moscow recognized Ukraine's breakaway regions - Donetsk and Luhansk - as independent entities.

Several countries including the UK, the US, Canada, and the European Union have condemned Russia's military operations in Ukraine and imposed sanctions on Moscow.

These countries have also promised Ukraine to help with military aid to fight Russia.