Jornal Do Brasilia - No breakthrough in Ukraine talks as Russian forces advance on Kyiv

After talks with Russian counterpart Sergei Lavrov in Turkey, Ukraine's Foreign Minister Dmytro Kuleba said there had been "no progress", even on a 24-hour ceasefire, although Lavrov said Moscow would keep talking.

Russian forces were encircling at least four major cities in Ukraine on Thursday, with armoured vehicles rolling up to the northeastern edge of the capital Kyiv.

Kyiv mayor Vitali Klitschko said half the population had fled, adding that the city "has been transformed into a fortress. Every street, every building, every checkpoint has been fortified."

The besieged southern port city of Mariupol meanwhile came under fresh attack, the day after the bombing of a children's hospital that local officials said killed three people, including a young girl.

Ukrainian President Volodymyr Zelensky said it was a Russian "war crime", a position backed by top European Union officials.

US Treasury Secretary Janet Yellen said the "intensifying" targeting of civilians could see Washington and its European allies step up already unprecedented sanctions on Moscow.

The Russian army however claimed the hospital bombing was a "staged provocation" by Ukraine.

At least 35,000 civilians were evacuated from the cities of Sumy, Enerhodar and areas around Kyiv on Wednesday, Zelensky said.

Around 2,000 more people left the eastern city of Izyum on Thursday, the deputy head of Zelensky's office, Kyrylo Tymoshenko, wrote on Telegram.

The situation in Mariupol is particularly dire, with ten days of constant attacks having left more than 1,200 civilians dead, according to the mayor.

The UN estimates more than 2.3 million refugees have left Ukraine since Russia shocked the world by invading its pro-Western neighbour on February 24.

- 'Barbaric' hospital attack -

The White House slammed the "barbaric" use of force against civilians, while EU foreign policy chief Joseph Borrell echoed Zelensky in calling the hospital attack a "heinous war crime".

Overall, at least 71 children have been killed in Ukraine since the start of the war, and more than 100 have been wounded, said Lyudmyla Denisova, the Ukraine parliament's point person on human rights.

Zelensky shared footage on Wednesday of massive destruction at the hospital, saying the "direct strike by Russian troops" had left children under the wreckage.

The United Nations said that two other Ukrainian maternity hospitals had been attacked and destroyed before the strike on Mariupol.

The city council reported new Russian air attacks Thursday on residential buildings in Mariupol, which aid agencies say is facing an "apocalyptic" situation, with no water, power or heat for more than a week.

Russia's foreign ministry on Wednesday did not deny the attack on the hospital but accused Ukrainian "nationalist battalions" of using it to set up firing positions after moving out staff and patients.

Lavrov reiterated the claim on Thursday, but Russian defence ministry spokesman Igor Konashenkov then put the blame on Kyiv.

"The Russian aviation carried out absolutely no missions to hit targets on the ground in the Mariupol area," Konashenkov said.

"The air strike that allegedly took place is a completely staged provocation to maintain anti-Russian hype for a Western audience."

Asked by a Turkish reporter if Russia was planning to attack other nations, Lavrov replied "we don't plan to attack other countries" and claimed "we did not attack Ukraine".

He insisted that Russian President Vladimir Putin launched the operation as the situation in Ukraine "posed a direct threat to the Russian Federation".

- 'Nowhere to run' -

On the northeastern edge of Kyiv, Ukrainian soldiers described a night of heavy battles for control of the main highway leading into the capital.

An AFP team witnessed missile strikes in Velyka Dymerka, a village just outside Kyiv's city limits.

Ukrainian forces only had a minimal presence in the village, which locals said witnessed heavy fighting overnight.

"It's frightening, but what can you do, there is nowhere to really run or hide. We live here," said Vasyl Popov, a 38-year-old advertising salesman.

Across Ukraine, the invasion has so far destroyed about $100 billion in roads, bridges and businessess, said Oleg Ustenko, chief economic advisor to Zelensky.

The conflict has raised fears of a nuclear accident in a country with major nuclear plants and the site of the Chernobyl disaster.

The UN's atomic watchdog, the International Atomic Energy Agency, said Wednesday it saw "no critical impact on safety" at Chernobyl, location of the world's worst nuclear disaster in 1986, after a loss of power there.

But it warned it was not receiving updates from either Chernobyl or Zaporizhzhia, Europe's largest nuclear plant, which is also now under Russian control.

The United States meanwhile rejected Russian claims that it was involved in bioweapons research in Ukraine, and warned Russia could be preparing to use chemical or biological weapons in the war.

- Chelsea owner targeted -

Washington has strongly backed Ukraine, leading the push for tough international sanctions and sending weapons and other aid.

But it has ruled out enforcing a no-fly zone and rejected a Polish plan to transfer fighter jets via a US air base for fear of being drawn into the conflict directly.

On Thursday, Lavrov said the supply by the EU and other countries of deadly weapons to Ukraine was "creating a colossal danger for themselves".

The US House of Representatives green-lit a spending package including nearly $14 billion for Ukraine and allies in eastern Europe, which must be rubber-stamped by the Senate.

The International Monetary Fund has meanwhile approved a $1.4-billion emergency package for Kyiv to provide "critical financial support".

Western sanctions have targeted Russia's financial system and its oligarchs, including Roman Abramovich, owner of football club Chelsea, who was on Thursday hit by a UK assets freeze and travel ban.

Treasury Secretary Yellen said Thursday the US and its allies were considering further sanctions because "the atrocities that they're committing against civilians seem to be intensifying".

Britain urged the entire G7 to follow suit, but some nations are wary, with Germany and Italy both dependent on Russian energy.

Putin on Thursday said Moscow was continuing to export oil and gas, including through Ukraine.

But he warned food prices will soar because of sanctions since Moscow is one of the world's top fertiliser producers.

burs-ar/ah

H. de Araujo--JDB