Street fighting engulfed various districts in Kyiv, with Ukrainian servicemen remarkably slowing the advance of a Russian contingent vastly outnumbering them and moving into the city as President Volodymyr Zelensky vowed to remain in place.

The city of 3 million endured a second night of shelling, with residents hunkering down in basement shelters and the city’s deep underground metro.

Zelensky appeared in videos through the evening to dispel suggestions that he had gone to the ground.  On Friday, he had called for talks with Russia to end the carnage, but denied any suggestion of surrender. Putin made it plain that he wanted Zelensky overthrown, calling on Ukrainian servicemen to stage a coup against a leadership made up of “Nazis and drug addicts.”

Western countries, led by the United States, slapped a new round of sanctions on Moscow, including punitive measures targeting Putin and Russian Foreign Minister Sergei Lavrov. At the United Nations, Russia predictably vetoed a U.N. Security Council motion denouncing the invasion.

As morning broke in Kyiv, pictures and video footage appeared of clashes near the city centre and of shells striking and considerable damage to a variety of sites. One photo showed a tower block with apartments on several floors all but destroyed.

Casualty figures were impossible to verify but it was clear that Ukraine’s armed forces were effective in their resistance. Ukraine’s military said 3,500 Russian servicemen had been killed since the military poured into the country from three directions on Thursday. Several aircraft had been downed, including two large Il-76 transport planes – one outside Kyiv and the other near Bila Tserkva further south.

Eyewitness accounts detailed hours of fighting around an airfield linked to the Antonov design bureau responsible for producing an army which left the facility in Russian hands without being certain the military could use it to its advantage to pour in troops.

Ukraine’s Health Ministry 198 Ukrainians had died so far in the Russian assault, including three children, though it was unclear whether the figures referred to civilians or military. The ministry said 1,115 had been injured, including 33 children.

Putin has said that the invasion was needed to address the problem of Russia being subjected to increasing pressure from NATO’s presence in eastern Europe three decades after the collapse of Soviet rule.

The notion of NATO membership, entrenched in Ukraine’s constitution, is at the root of Putin’s decision to push into his neighbour’s territory. Russia denied for weeks it had plans to invade as it engineered a buildup of more than 100,000 troops on the Ukrainian border, but Putin complained that Western countries had all but dismissed his calls for security guarantees – including an undertaking that NATO would expand no further and Ukraine would never be allowed to join.

NATO members have been providing Ukraine with a variety of lethal weaponry. But Biden, and other NATO leaders, had made it plain that they were not prepared to dispatch troops to Ukraine.

Late-night videos in central Kyiv

Zelensky appeared on video alongside top advisers in the middle of the night outside his office in the city centre.

“We are here,” Zelensky, wearing military green, said in front of the presidency building flanked by his top advisers. “We are in Kyiv. We are protecting Ukraine.”

Earlier in the evening, the president had posted another video warning Kyiv residents of a difficult night ahead.

“This night will be the hardest,” he said. “This night the enemy will be using all available means to break our resistance. This night they will launch an assault.”

Zelensky also issued a direct appeal to Putin for talks to secure a cease-fire.

Speaking in Russian, Zelensky said: “I would like to address the President of the Russian Federation once again. There is fighting all over Ukraine now. Let’s sit down at the negotiation table to stop the people’s deaths.”

The Kremlin said it was willing to have talks – in Minsk, capital of Russian ally Belarus, one of the three points of departure for troops pouring over the border into Ukraine. Ukraine rejected the proposed venue. Talks aimed at ending eight years of conflict that have killed 14,000 in eastern Ukraine have taken place in Minsk.

Putin, addressing a session of Russia’s Security Council shown on television, used a reference to Ukrainian World War Two insurgent leader Stepan Bandera in making it plain his primary aim was to topple the president. He told Ukrainian soldiers to stage a coup.

“Once again I speak to the Ukrainian soldiers,” he said. “Do not allow neo-Nazis and Banderites to use your children, your wives and the elderly as a human shield. Take power into your own hands. It seems that it will be easier for us to come to an agreement than with this gang of drug addicts and neo-Nazis.”

Eight years after Russia annexed Crimea and fomented a rebellion in eastern Ukraine,  Putin has repeatedly accused authorities in Kyiv of committing “genocide” against Russian speakers in the east of the country.

New sanctions, refugees pour out of Ukrainian cities

Western leaders, horrified by the looming carnage, adopted a new set of sanctions against Russia. Joined by Britain, Canada and the European Union, these measures target the personal assets of Putin and veteran Foreign Minister Sergei Lavrov. Analysts said the moves, while high-profile, were largely symbolic and would have little effect on either man.

The United Nations sounded the alarm on the growing flood of refugees heading out of Kyiv and other major cities and hoping to cross an international border to safety.

“More than 50,000 Ukrainian refugees have fled their country in less than 48 hours – a majority to Poland and Moldova,” the head of the U.N. refugee agency, Filippo Grandi, said in a tweet. “Many more are moving towards its borders.”

At the U.N. Security Council session, Western countries led by the United States lamented the rejection of the motion by Russia, a permanent Council member with veto power.

The vote was 11 in favour, with Russia voting no and China, India and the United Arab Emirates abstaining, exposing the degree of opposition to Putin.

The United States said the Russian invasion was precisely the sort of situation for which the 15-member Council was created.

“But let me make one thing clear: Russia, you can veto this resolution, but you cannot veto our voices,” U.S. Ambassador Linda Thomas-Greenfield said told her Russian counterpart. “You cannot veto the truth. You cannot veto our principles. You cannot veto the Ukrainian people.”