Ukrainian President Volodymyr Zelenskiy called on Saturday for comprehensive peace talks with Moscow and also urged Switzerland to do more to crack down on Russian oligarchs who he said were helping wage war on his country with their money.

British intelligence warned that Russia, frustrated by its failure to achieve its objectives since it launched the invasion on February 24, was now pursuing a strategy of attrition that could exacerbate the humanitarian crisis.

Russian forces have taken heavy losses and their advance has largely stalled since President Vladimir Putin launched the assault, with long columns of troops that bore down on Kyiv halted in the suburbs.

But they have laid siege to cities, blasting urban areas to rubble, and in recent days have intensified missile attacks on scattered targets in western Ukraine, away from the main battlefields.

Zelenskiy, who makes frequent impassioned appeals to foreign audiences for help for his country, told an anti-war protest in Bern that Swiss banks were where the "money of the people who unleashed this war" lay and their accounts should be frozen.

Ukrainian cities “are being destroyed on the orders of people who live in European, in beautiful Swiss towns, who enjoy property in your cities. It would really be good to strip them of this privilege,” he said in an audio address.

Neutral Switzerland, which is not a member of the European Union, has fully adopted EU sanctions against Russian individuals and entities, including orders to freeze their wealth in Swiss banks.

The EU measures are part of a wider sanctions effort by Western nations, criticized by China, aimed at squeezing Russia’s economy and starving its war machine.

In an address earlier on Saturday, Zelenskiy urged Moscow to hold peace talks now.

“I want everyone to hear me now, especially in Moscow. The time has come for a meeting, it is time to talk,” he said in a video address. “The time has come to restore territorial integrity and justice for Ukraine. Otherwise, Russia’s losses will be such that it will take you several generations to recover.”

Britain’s defense attache to the United States said British intelligence believes Russia has been taken aback by the Ukrainian resistance to its assault and has so far failed to achieve its original objectives.

“Russia has been forced to change its operational approach and is now pursuing a strategy of attrition” likely to involve the “indiscriminate use of firepower resulting in increased civilian casualties,” Air Vice Marshal Mick Smeath said in a statement.

Putin, who calls the action a “special operation” aimed at demilitarizing Ukraine and purging it of what he sees as dangerous nationalists, told a rally on Friday in Moscow that all the Kremlin's aims would be achieved.

On Saturday, Russia said its hypersonic missiles had destroyed a large underground depot for missiles and aircraft ammunition in the western Ivano-Frankivsk region. Hypersonic weapons can travel faster than five times the speed of sound, and the Interfax agency said it was the first time Russia had used them in Ukraine.

A spokesperson for the Ukrainian Air Force Command confirmed the attack, but said the Ukrainian side had no information on the type of missiles used.

Ukraine’s defense ministry said in its late Saturday night update that Russian forces continued their offensive in the eastern Donetsk region, but Russian troops were forced to regroup in some areas in Ukraine’s south and additional reserves were deployed there.

The ministry also said that the “moral and psychological condition of the (Russian) personnel is low and deteriorating with each passing day of hostilities.”

The Ukrainian military command in charge of forces in two breakaway regions of eastern Ukraine said they had fought off 10 attacks on Saturday, destroying a total of 28 tanks, armored personnel carriers and armored cars and killing more than 100 soldiers. Reuters was unable to independently corroborate the claim.

The UN human rights office said at least 847 civilians had been killed and 1,399 wounded in Ukraine as of Friday, with the real figure likely much higher. The Ukrainian prosecutor general's office said 112 children were among the dead. Russia says it is not targeting civilians.

Kyiv authorities said on Saturday that 228 people had been killed in the capital since Russia's invasion began, including four children.

A further 912 people have been wounded, the Kyiv city administration said in a statement.

Reuters has not been able to independently confirm casualty figures.

‘Know how to Fight’

Ordinary Ukrainians have joined the effort to defend their country, such as at a training facility in Odessa, a picturesque, multicultural Black Sea port, where young urban professionals were learning about handling weapons and applying first aid.

“Every person should know how to fight, how to make medicine,” said 26-year-old graphic designer Olga Moroz.

More than 3.3 million refugees have fled Ukraine through its western border, with around 2 more million displaced inside the country. Ukraine has evacuated 190,000 civilians from front-line areas via humanitarian corridors, Deputy Prime Minister Iryna Vereshchuk said on Saturday.

“I'll go (to Germany) for three weeks but I hope I can go home after that,” said Olga Pavlovska, a 28-year-old refugee in the Polish town of Przemysl, hoping Zelekskiy's calls for comprehensive peace talks will end the invasion.

Hundreds of thousands have been trapped in the port city of Mariupol for more than two weeks with power, water and heat supplies cut off. Bodies amid the rubble are a common sight. Local officials say fighting has reached the city center and heavy shelling kept humanitarian aid from getting in.

About 600 residential buildings in the eastern Ukrainian city of Kharkiv have been destroyed and are unfit for habitation since the start of the Russian invasion, Kharkiv's regional governor Oleh Synyehubov said.

Rescue workers were still searching for survivors in a Mariupol theater that authorities say was flattened by Russian air strikes on Wednesday. Russia denies hitting the theater.

Interfax quoted Russian Foreign Minister Sergei Lavrov as saying Moscow expected its operation in Ukraine to end with a signing of a comprehensive agreement on security issues, including Ukraine's neutral status.

Kyiv and Moscow reported some progress in talks this week toward a political formula that would guarantee Ukraine's security, while keeping it outside NATO, though both sides accused each other of dragging things out.

China has not condemned Russia's invasion, though it has expressed concern about the war.

Chinese Vice Foreign Minister Le Yucheng said on Saturday that Western sanctions against Russia were getting "more and more outrageous." read more