Firefighters work to extinguish the flames at a supermarket following a Russian airstrike on Kramatorsk in Donetsk, Ukraine, on July 4, 2026. Photo: VCG

Russian President Vladimir Putin and Ukrainian President Volodymyr Zelensky held separate telephone conversations with US President Donald Trump on Saturday, which is the US Independence Day, to discuss the Ukraine conflict ahead of a NATO summit in Ankara, Russian presidential aide Yuri Ushakov and Zelensky said. 

Trump's separate phone calls with Putin and Zelensky were primarily aimed at probing and assessing the stalled Russia-Ukraine diplomatic negotiations, a Chinese expert said. The Ukraine issue is not only a difficult problem for Putin and Zelensky, but also an unavoidable and complex challenge for Europe and NATO as a whole. From the US side, maintaining communication with both parties is mainly intended to signal, ahead of the NATO summit, that US remains engaged and present in the process, while not significantly increasing its level of intervention or commitment. 

During the dialogue, Putin laid out the real battlefield situation, where Russian troops are advancing along the entire line of contact. Ushakov stressed that European nations hold a flawed perception of the overall dynamics and ground realities along the contact line amid the Ukraine conflict, Xinhua reported. 

On bilateral ties, Putin and Trump underscored the importance of sustaining consistent communication, including on military-political and economic fronts. 

"There exist vast prospects for mutually beneficial cooperation between our two nations in these spheres. Trump stressed that an early resolution to the Ukraine conflict would be a prerequisite for unlocking such cooperation," Ushakov said, according to Xinhua. 

According to Ushakov, the US president said that US envoys Steve Witkoff and Jared Kushner would continue their efforts at brokering a settlement and were prepared to make another visit to Moscow, The Moscow Times reported on Sunday. 

Zelensky said on X that he had spoken to Trump on the Fourth of July holiday and called for "American resolve" to help end the more than four-year-old conflict with Russia. Zelensky said he had a "very good" conversation with Trump, discussing the situation on the front line, The Straits Times reported on Sunday. 

"President Trump and I discussed the current situation on the frontline as well as our diplomatic efforts. There is a real prospect to put an end to this war, and America's resolve is decisive. We have agreed to continue these discussions during the NATO Summit in Ankara," he wrote on X, Le Monde reported. 

Russia claimed on Friday that its armed forces had taken full control of the city of Konstantinovka in eastern Ukraine. "The main news is that Konstantinovka has been completely taken," Kremlin spokesperson Dmitry Peskov was quoted by RIA Novosti as saying, Xinhua reported. 

The Russian air defense forces shot down 72 Ukrainian drones in the Leningrad region Saturday morning, said regional Governor Alexander Drozdenko, according to Xinhua.

Diplomatically, negotiations are at an impasse, with Moscow demanding the withdrawal of Ukrainian forces from the entire Donetsk region - a demand that Kyiv rejects, according to Le Monde. 

Heads of state and delegations from 32 countries, including Trump, are expected to arrive in Ankara starting Tuesday for the NATO summit, Le Monde reported. 

Trump's separate calls with Putin and Zelensky focused on the stalled Russia-Ukraine peace talks, which remain a key issue for both leaders, as well as Europe ahead of the NATO summit, Zhang Hong, a research fellow at the Institute of Russian, Eastern European and Central Asian Studies at the Chinese Academy of Social Sciences, told the Global Times on Sunday. 

The calls were primarily intended to gauge the latest developments and understand the current positions of both sides, including any shifts in Russia's negotiating demands and stance, essentially serving as a process of probing and testing the situation, Zhang said. 

Trump's call with Zelensky came amid US-Europe differences over the Russia-Ukraine conflict, which remains a difficult challenge for NATO. The outreach ahead of the NATO summit is seen as a cautious effort to manage tensions and avoid escalation, Zhang said.

Trump's calls with both sides are seen as a symbolic effort to maintain US engagement without heavy involvement, ahead of consultations with Europe on Ukraine. The move is viewed as preparatory technical and diplomatic groundwork rather than a substantive policy shift, Zhang added.