Officials in the Ukrainian port city of Mariupol, which is surrounded by Russian forces, said on Saturday (Mar 3) they were delaying an evacuation of the civilian population, accusing Moscow's troops of breaking a ceasefire. "Due to the fact that the Russian side does not adhere to the ceasefire and has continued shelling both of Mariupol itself and its environs and for security reasons, the evacuation of the civilian population has been postponed," city officials said in a statement on social media.

Mariupol, a southern city of about 450,000 people on the Azov Sea, was scheduled to begin the evacuations at 0900 GMT, after Russian forces agreed a ceasefire to allow civilians to leave the fighting. "We ask all Mariupol residents to disperse and head to places where they can shelter.

More information about the evacuation will be posted soon," municipal officials wrote. "At the moment, negotiations are underway with Russia to establish a ceasefire and ensure a safe humanitarian corridor," the statement added. But Russia's defence ministry accused Ukraine nationalists in Mariupol and Volnovakha of blocking Ukrainians from leaving towards Russia.

"The same is happening in Kharkiv and Sumy, as well as in a number of other settlements," the defence ministry said in a statement, referring to two other cities in eastern Ukraine at the centre of fighting. It also said it had respected the ceasefire and accused Ukrainian forces of shoring up defences during the halt in fighting. Earlier on Saturday, the city hall had announced on social media that said "it will be possible to leave the city by private transport."

"A huge request to all drivers leaving the city, to contribute as much as possible to the evacuation of the civilian population - take people with you, fill vehicles as much as possible," the statement said. The announcement said the evacuation would last over several days to allow the entirety of the civilian population to exit the city.

In the statement, city officials told residents leaving in private vehicles that it was "strictly prohibited" to go off course from the evacuation routes. Municipal buses were also departing from three locations in the city to help people leave, the message said. Ukraine Deputy Prime Minister Iryna Vereshchuk also wrote on social media that some 200,000 people were expected to be extracted from the city.

She said that a further 15,000 people would be brought from Volnovakha, a town of around 20,000 people some 60km (38 miles) from separatist-controlled Donetsk, a regional centre. The Russian defence ministry earlier announced a ceasefire regime from 0700 GMT to allow for evacuations.