KYIV -- A defiant President Volodymyr Zelensky said Kyiv remained under Ukrainian control on Saturday as Russian forces renewed their assault, pounding the capital and other cities with artillery and cruise missiles.

A U.S. defense official said Ukraine's forces were putting up "very determined resistance" to the three-pronged Russian advance that has sent hundreds of thousands of Ukrainians fleeing westwards, clogging major .highwaysand railway 

"We have withstood and are successfully repelling enemy attacks. The fighting goes on," Zelenskiy said in a video message from the streets of Kyiv posted on his social media

Russian President Vladimir Putin launched what he called a special military operation before dawn on Thursday, ignoring Western warnings and saying the "neo-Nazis" ruling Ukraine threatened Russia's security.

The Kremlin said its troops were advancing again after Putin ordered a pause on Friday for anticipated talks that never happened. An adviser to Zelensky denied that Kyiv had refused negotiations but said Russia had attached unacceptable conditions. He also said it was untrue that Russia had paused troop movements.

Russia's assault is the biggest on a European state since the Second World War and threatens to upend the continent's post-Cold War order.

The crisis has galvanized the NATO Western military alliance, which has announced a series of moves to reinforce its eastern flank. While NATO has said it will not deploy troops to Ukraine, a string of countries are sending military aid.

U.S. President Joe Biden approved the release of up to US$350 million worth of weapons from U.S. stocks, while Germany, in a shift from its long-standing policy of not exporting weapons to war zones, said it would send anti-tank weapons and surface-to-air missiles. Read full storyRead full storyRead full story

MISSILE STRIKES

Ukraine, a democratic nation of 44 million people, won independence from Moscow in 1991 after the fall of the Soviet Union and wants to join NATO and the EU, goals Russia opposes.

Putin has said he must eliminate what he calls a serious threat to his country from its smaller neighbour, accusing it of genocide against Russian-speakers in eastern Ukraine - a charge dismissed by Kyiv and its Western allies as baseless propaganda.

The United States has observed more than 250 launches of Russian missiles, mostly short-range, at Ukrainian targets, the U.S. defence official said.

"We know that (Russian forces) have not made the progress that they wanted to make, particularly in the north. They have been frustrated by what they have seen is a very determined resistance," the official said, without providing evidence.

Chechen leader Ramzan Kadyrov, a close Putin ally, said on Saturday his fighters were also deployed in Ukraine. He said Russian forces could easily take Kyiv and other large cities but their task was to avoid loss of life.

Kyiv's mayor Vitali Klitschko said there was no major Russian military presence in the capital, but that saboteur groups were active. The metro system was being used as a shelter for citizens and trains have stopped running, he said.

Klitschko, a former world heavyweight boxing champion, said 35 people, including two children, had been wounded overnight and that he was imposing a curfew from Saturday evening until Monday morning.

Ukrainians faced lengthy queues for money at cash machines and for fuel at petrol stations, where individual sales are mostly limited to 20 litres. Many shops in the city centre were closed and the streets were largely empty on Saturday afternoon.

"I was smart enough to stock up food for at least a month," said Serhiy, out for a walk before the curfew. "I did not trust the politicians that this would end peacefully."

At least 198 Ukrainians, including three children, have been killed and 1,115 people wounded so far in Russia's invasion, Interfax quoted Ukraine's Health Ministry as saying. It was unclear whether the numbers comprised only civilian casualties.

Interfax later cited the regional administration in Donetsk, eastern Ukraine, saying 17 civilians had been killed and 73 wounded by Russian shelling.

Moscow says it is taking care not to hit civilian sites.

A Ukrainian presidential adviser said about 3,500 Russian soldiers had been killed or wounded. Western officials have also said intelligence shows Russia suffering higher casualties than expected, but such tolls were impossible to verify. Russia has not released casualty figures.