by Dave CLARK and Daphne ROUSSEAU
Kyiv - Russian President Vladimir Putin on Saturday warned the West of a wider war if a no-fly zone is set up, as his forces resumed an offensive against a key Ukrainian city where a planned evacuation of residents failed to take place over security fears.
With his Ukrainian counterpart Volodymyr Zelensky criticising NATO for ruling out a no-fly zone for fear of sparking nuclear conflict, Putin spoke of "colossal and catastrophic consequences not only for Europe but also the whole world", if such a zone was set up.
"Any movement in this direction will be considered by us as participation in an armed conflict by that country," Putin said.
For Zelensky, on day 10 of the invasion, under an escalating bombardment that has flattened more and more infrastructure and sent nearly 1.4 million civilians fleeing for their lives, the Western military alliance's "no" to a no-fly zone had essentially given "the green light for further bombing of Ukrainian cities and villages".
The strategic city of Mariupol proudly resisted Moscow-backed rebels during a 2014 conflict, but the Azoz sea port has for days been without electricity, food and water in the dead of winter and people began gathering for the evacuation.
After Russia's defence ministry declared the ceasefire -- to open a humanitarian corridor out of the war's fiercest battles -- officials said the city's 450,000-strong population could begin to leave by bus and private cars.
However city officials then called a delay in the evacuation, saying: "The Russian side does not adhere to the ceasefire and has continued shelling both Mariupol itself and its environs, and for security reasons, the evacuation of the civilian population has been postponed."
Russia later announced the assault was back on.
"Due to the unwillingness of the Ukrainian side to influence nationalists or extend the ceasefire, offensive actions have been resumed," at 1500 GMT a Russian defence ministry spokesman said.
The siege came as more Russian forces inched closer to the capital.
The western edge of Kyiv bears witness to a human tragedy whose scale grows ever greater as Russia's assault becomes more determined and indiscriminate.
Working class towns such as Bucha and Irpin are in the line of fire and air raids on Friday broke many people's resolve to stay.
"Warplanes. They are bombing residential areas -- schools, churches, big buildings, everything," said accountant Natalia Dydenko said after a quick glance back at the destruction she left behind.
Dozens of civilians have been killed in assaults on the northern town Chernihiv. Those remaining live among the town's ruins and in craters.
Scenes of devastation
"There were corpses all over the ground," Sergei told AFP, as air raid sirens wailed once more. "They were queueing here for the pharmacy that's just there, and they're all dead."
AFP reporters saw scenes of devastation -- despite Moscow's insistence it is not targeting civilian areas.
Zelensky remains defiant, announcing Saturday that Ukrainian forces were counter-attacking around Kharkiv, the country's second largest city, which has seen Russian incursions and fierce bombardments.
"We inflict such losses on the invaders that they have not seen even in their worst dream," he said.
Since Putin's army invaded on February 24, Russia has pummelled Ukrainian cities, with officials reporting hundreds of civilians killed. Europe's largest atomic power plant has even come under attack sparking fears of a catastrophic nuclear accident.
But Moscow has so far only seized two key cities in its 10-day-long invasion -- Berdiansk and Kherson on Ukraine's southern Black Sea coast.
Capturing Mariupol represents a bigger prize for Russian forces as it would deal a severe blow to Ukraine's maritime access and connect with troops coming from annexed Crimea and the Donbas.
The Kremlin said it was waiting for a third round of talks with Ukraine in Belarus, and one of Kyiv's negotiators said it hoped to hold them this weekend.
A third round of talks would take place on Monday, the Ukrainian side said on Saturday.
Zelensky was to appeal to Washington for more assistance Saturday with an address to the US Senate after some lawmakers urged President Joe Biden to take tougher measures, including banning Russia's oil imports.
With fears growing of direct conflict between NATO and Russia -- both nuclear armed -- the US and Moscow have set up a new direct phone line to reduce the risks of "miscalculation", the Pentagon said Friday.
US chairman of the joint chiefs of staff General Mark Willey became the latest Western figure to rule out a no-fly zone, saying it would mean taking on Russian air forces.
"That is not something that NATO Secretary General (Jens) Stoltenberg or any member states senior political leadership has indicated that they want to do," Milley told reporters in Riga.
Russian authorities have imposed a news blackout and multiple media outlets have halted operations. Twitter was restricted and Facebook blocked in Russia.
A host of news outlets including the BBC, and Bloomberg said they were suspending work in Russia after lawmakers in Moscow passed legislation to impose fines and jail terms of up to 15 years for publishing "fake news" about the army.
CNN said it would halt broadcasting in Russia, while independent Russian newspaper Novaya Gazeta said it would remove Ukraine content.
The Kremlin on Saturday defended the new law, saying it was "necessary as the country was facing "an unprecedented information war".
- Global hunger -
Putin has been unmoved as Russia has become isolated in economic, sporting and cultural fields.
But that did not stop tens of thousands of people from taking to the streets of cities across Europe, from Berlin, to London, Geneva to Paris, Prague Madrid and Vilnius to protest against the invasion.
And the list of major companies suspending operations in Russia grew again with Spanish clothing giant and Zara fast-fashion chain owner Inditex calling a halt.
Flagship airline Aeroflot said it was suspending all its international flights from March 8, citing "circumstances that impede the operation of flights".