Finland on Saturday sought to allay Moscow's fears about its bid to join NATO, as fierce fighting raged in Ukraine's east, slowing down a hoped-for Russian advance.
Wives and parents of Ukrainian fighters trapped in the bowels of a besieged steel plant in the country's south meanwhile made a desperate appeal to China to help secure their release.
And the G7 vowed to further turn the screw on the Kremlin with fresh sanctions, pledging never to recognise the borders it was attempting to redraw through destructive force.
One of Europe's fiercest conflicts since World War II has seen more than six million people flee for their lives, and according to Kyiv has caused an estimated $90 billion in damage to civilian infrastructure.
US Defence Secretary Lloyd Austin urged his Russian counterpart Sergei Shoigu to move immediately to implement a ceasefire, in their first talks since the conflict began on February 24.
But one senior Ukrainian general predicted a turning point in the months ahead, and that the fighting could be over by the end of the year.
In Turin, Italy, a world away from the fighting, a wave of popular support has made Ukraine's Kalush Orchestra the bookmakers' favourite to triumph at the world's biggest live music event -- the Eurovision Song Contest.
But even here the war has cast a shadow.
"We have one band member who joined the territorial defence of Kyiv on the third day of the war," said lead singer Oleh Psiuk.
"We are very worried about him, and we hope to see him safe once we are back."
Finland and Sweden are poised to jettison decades of military non-alignment to join NATO as a defence against feared further aggression from Russia.
Moscow has warned Finland, with whom it shares a 1,300-kilometre (800-mile) border, that it would take "reciprocal steps".
Hours after Finland's grid operator said Russia had pulled the plug on electricity supplies overnight, President Sauli Niinisto had a "direct and straight-forward" conversation by phone with Vladimir Putin
"Avoiding tensions was considered important," Niinisto's office said. "The phone call was initiated by Finland."
Putin, however, told him that Finland joining NATO would be a "mistake", insisting that Russia posed "no threat to Finland's security", the Kremlin said.
Finland's bid to join NATO is expected to be announced this weekend.
In Ukraine, the government and military claimed it was holding back a Russian assault in the strategic eastern Donbas region, stifling Moscow's attempt to annex the south and east.
Russia, which sent in troops to Ukraine on February 24, has increasingly turned its attention to eastern Ukraine since the end of March, after failing to take the capital Kyiv.
The governor of the eastern Lugansk region, Serhiy Gaidai, said Ukrainian forces had prevented Russian attempts to cross a river and encircle the city of Severodonetsk.
Defence and military intelligence officials in London and Washington both said Russian forces had sustained heavy losses as they attempted the river crossing and had failed to make significant progress.
The Ukrainian General Staff said troops had managed to push Russian troops out of Ukraine's second city of Kharkiv in the northeast -- a priority target for Moscow.
"The enemy's main efforts are focused on ensuring the withdrawal of its units from the city of Kharkiv," a spokesman said.
Kharkiv regional governor Oleh Synegubov meanwhile said in a video on Telegram that Ukrainian forces were counter-attacking in the direction of the northeastern city of Izyum.
Ukraine's military intelligence chief, Major General Kyrylo Budanov, said the months ahead would be decisive for the course of the war.
"The breaking point will be in the second part of August," he told Britain's Sky News television.
"Most of the active combat actions will have finished by the end of this year."
Ukrainian President Volodymyr Zelensky on Saturday met Mitch McConnell, leader of the Republican minority in the US Senate, and a delegation of US senators in Kyiv.
On Friday Zelensky said his troops would fight to recapture all occupied territory, and those under siege, including in the devastated southern port city of Mariupol.
There, the last defenders of the city are holed up in a warren of underground tunnels and bunkers at the vast Azovstal steelworks under heavy bombardment.
The United Nations and Red Cross helped to evacuate women, children and the elderly from the plant whey there were sheltering earlier this month.
But local officials said around 600 fighters from Ukraine's Azov regiment were wounded and needed to be brought out for medical treatment.
In Kyiv, five wives and a father of fighters trapped at the plant appealed directly to China's President Xi Jinping to step in.
"China has a big influence on Russia and on Putin personally. We ask for him to intervene," said one man, Stavr Vychniak.