Ukrainian officials say Russia has continued to strike Ukraine's energy facilities despite US President Donald Trump's announcement that the countries had agreed on an "energy ceasefire".
On Monday a statement from the Regional Prosecutor's Office of Kharkiv said Russian forces had attacked an energy facility on the outskirts of the city.
That came after Ukrainian President Volodymyr Zelenskyy said he "welcomed" Mr Trump's announcement, but Russia was still hitting energy infrastructure in Kyiv and Kharkiv.
Mr Trump's brief social media post on Sunday announcing the purported agreement to mutually cease attacks on energy sites said that the ceasefire took effect immediately.
"Do not break it!" the post said.
Residents take a shelter in a basement of an apartment building during a threat of a Russian drone strike in Kharkiv. (Reuters: Vyacheslav Madiyevskyy)
Mr Trump also claimed in a social media post on September 14 that both countries had agreed "not to hit" each other's energy infrastructure, but offered no details on that proposal either. Nothing came of the purported agreement.
Australia is joining other nations in backing the "energy ceasefire" while urging Moscow to "end its unjustified and unprovoked invasion" of its neighbour.
"Australia supports an energy ceasefire which is respected by Russia and contributes towards a just and lasting peace, on Ukraine's terms," a Department of Foreign Affairs and Trade (DFAT) spokesperson said.
Local officials say least 12 people were wounded in several Russian attacks on Kharkiv on Monday morning.
Kharkiv Mayor Ihor Terekhov said drones struck a high-rise building in what is Ukraine's second-largest city.
This damaged Kharkiv apartment building is a sign that Russia wants to "weaponise winter", Ukrainian officials say. (Reuters: Sofiia Gatilova)
Floors seven through to nine of the building were destroyed in the attack, Mr Terekhov said, adding that there was an intense fire at the scene.
Russia has used attacks on energy facilities in order to deny Ukrainian civilians power, heat and running water during the war, hoping to wear down public resistance to Moscow's invasion.
Ukrainian officials describe the strategy as "weaponising winter".
Ukraine, meanwhile, has levelled strikes against Russian energy sites such as oil refineries, sometimes deep within Russian territory.
Such actions prompted Mr Trump to blame Mr Zelenskyy for high diesel prices in the US weeks ahead of the midterm elections.
'Stop killing our people'
Mr Zelenskyy said Kyiv was ready to comply with Mr Trump's requests to stop striking Russian refineries if Moscow halted attacks on Ukraine's energy system. He asked Mr Trump to press the Kremlin to agree.
"We are ready to respect an energy ceasefire if Russia is ready to do the same. We agree, if they agree," Mr Zelenskyy said.
"If Russia wants us to stop our long-range strikes against its oil refineries and oil exports, then Russia must stop its strikes against our energy system and critical infrastructure, and stop killing our people. This is only fair."
Volodymyr Zelenskiy speaks during the Warsaw Security Forum in Poland on Monday. (Reuters: Aleksandra Szmigiel)
Mr Zelenskyy made the comments in Poland on Monday at the opening of the Warsaw Security Forum, where government officials, military leaders and experts discussed security challenges, NATO policy and regional stability.
Mr Zelenskyy added that he was "grateful to America", but lamented that "this is Putin's answer to Trump: Russian attacks".
"It was clear that Putin does not read Truth Social," he said.
"This winter, if Russia does not agree to an energy ceasefire, we will respond."
Earlier, the European Union's top diplomat welcomed the prospect of a pause in energy strikes in Ukraine, but said she saw no sign that Russia would be willing to respect it.
"We haven't yet seen that also Russia will stick to it," EU foreign policy chief Kaja Kallas said at a meeting of the bloc's foreign ministers in Luxembourg.
"Personally, I would also welcome that the ceasefire would include people not being killed, not only energy."
Wires/ABC