Zelenskyy said the “entire European project is a target for Russia” and “was not intended to be limited to Ukraine alone”. In his late-night address to Ukrainians on Saturday he also said that stopping the invasion of Ukraine is essential for the security of all democracies.

His address came as civilians continued to flee eastern parts of the country before an expected onslaught and firefighters searched for survivors in a northern town no longer occupied by Russian forces.

More Russian atrocities are revealed on a day to day basis as a grave with dozens of civilians were found in Buzova village near Kyiv, a Ukrainian official said, the latest reported mass grave to be discovered after Russian forces withdrew from areas north of the capital to focus their assault on the east.

Russia has repeatedly rejected allegations by Ukraine and Western countries that it targeted civilians in what it calls a "special operation" to demilitarise and "denazify" its southern neighbour.

Some cities in the east are under heavy shelling with tens of thousands of people unable to evacuate.

Zelensky in his Saturday address also renewed appeal to Western allies for a complete embargo on Russian energy products and more weapons for Ukraine.

British Prime Minister Boris Johnson met Zelenskiy in Kyiv on Saturday and pledged armoured vehicles and anti-ship missile systems, along with additional support for World Bank loans.

The European Union on Friday adopted new sanctions against Russia, including bans on the import of coal, wood, chemicals and other products. Oil and gas imports from Russia remain untouched.

But in the east, calls by Ukrainian officials for civilians to flee were given a greater sense of urgency by a missile attack on Friday on a train station in the city of Kramatorsk in the Donetsk region, Ukrainian officials said more than 50 people were killed in the attack.

Residents of the region of Luhansk would have nine trains on Sunday to get out on, the region's governor, Serhiy Gaidai, wrote on the Telegram message service.

Serhiy later said a school and a high-rise apartment building were shelled early on Sunday in the city of Sievierodonets.

Russia's invasion has forced about a quarter of Ukraine's 44 million people from their homes, turned cities into rubble and killed or injured thousands.
-Reuters/AP