Russia warned Kyiv residents to flee their homes Tuesday and rained rockets on the city of Kharkiv as Russian commanders intensified their bombardment of Ukrainian urban areas in a shift of tactics after their six-day assault stalled.
A US official said a miles-long armoured column bearing down on the capital Kyiv had not made any advances in the past 24 hours, frozen in place by logistics problems, short on fuel and food, and perhaps pausing to reassess tactics.


People march to protest against Russia's invasion of Ukraine in central Saint Petersburg, Russia


Russia's defence ministry said its forces would strike targets in Kyiv used by Ukraine's security service and also communications sites.
Speaking in a heavily guarded government compound in Kyiv, President Volodymyr Zelenskiy said Russia must "first stop bombing people" before peace talks could make any headway.
Zelenskiy also urged Nato members to impose a no-fly zone to stop Russia's airforce, something the military alliance has ruled out.
As Zelenskiy, unshaven and wearing simple khaki clothes, spoke, news came that a Russian missile had struck a TV tower near a Holocaust memorial site in Kyiv, killing five people.
Rocket strikes on Ukraine's second biggest city Kharkiv killed at least 10 people and wounded 35, Ukrainian Interior Ministry adviser Anton Herashchenko said.
Similar strikes killed and wounded dozens in Kharkiv on Monday.
Zelenskiy, who also spoke by phone for 30 minutes with US President Joe Biden , said the artillery barrages on Kharkiv, a city of 1.5 mn, amounted to "state terrorism".
Nearly a week since Russian troops poured over the border, they have not captured a single major Ukrainian city after running into far fiercer resistance than they expected.
Michael Kofman, an expert on the Russian military at Washington DC's Wilson Center, tweeted: "Looking at the Russian operation so far, they're having tremendous problems with logistics and communications. The whole effort seems shambolic."
Many Western military analysts fear that Russia will now fall back on tactics which call for crushing bombardment of built-up areas before trying to enter them.
The Russians have been surprised not only by the scale of Ukrainian resistance but also by poor morale among their own forces, some of whom surrendered without a fight, the US official said.
Russia's Defence Minister Sergei Shoigu said the "special military operation" would continue until it had achieved its goals, defined by Putin as disarming Ukraine and capturing the "neo-Nazis" he says are running the country.
Pictures released by US satellite company Maxar showed Russian tanks, artillery and fuel trucks stretching for 60 km along a highway to the north.
"For the enemy, Kyiv is the key target," Zelenskiy, who has remained in the capital rallying Ukrainians, said in a message overnight."We will neutralise them all."
In an emotional address to the European Parliament by video link , Zelenskiy urged the bloc to prove that it sided with Ukraine.
"Do prove that you will not let us go. Do prove that you are indeed Europeans and then life will win over death and light will win over darkness," he said.
More than 660,000 people, mostly women and children, have fled Ukraine to neighbouring countries such as Poland and Romania since the invasion began, the UN
refugee agency said.
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