Russia-Ukraine war: Hours after Trump-Putin phone call, Zelensky warns of Russian troop buildup

Ukrainian President Volodymyr Zelensky has warned that Russia is amassing troops along the Sumy front and preparing fresh offensives on the Zaporizhzhia, Sumy, and Kharkiv fronts to escalate pressure on Kyiv in the coming months, Al Jazeera reported on Wednesday.

He also noted that Ukrainian troops were continuing operations in Russia's Kursk region despite recent Russian offensives.

“Ukraine is fulfilling its task in the Kursk region. The Ukrainian military is there, and they will be there as long as we need this operation,” he said, as quoted by Al Jazeera.

Zelensky's warnings come a day after US President Donald Trump spoke to his Russian counterpart Vladimir Putin over a phone call, demanding a 30-day ceasefire in Ukraine. During the conversation, both leaders agreed to an immediate ceasefire on energy and infrastructure.

According to the Kremlin, Putin has already ordered his military to pause strikes against Ukraine's power grid for 30 days. A Kremlin statement also emphasised that Kyiv could not rearm or mobilise during any ceasefire.

Russia and Ukraine will also exchange 175 prisoners each on Wednesday “as a goodwill gesture”, with further talks to take place immediately in the Middle East.

Ukraine's stand on ceasefire

Zelensky said that he supports a 30-day pause in attacks on energy infrastructure but requires more details before Kyiv can fully endorse the proposal. He made these remarks on Tuesday while visiting Finnish President Alexander Stubb in Helsinki. He also said he’d agree to such an idea provided the US plays the role of middleman.

Russia and Ukraine accused each other on Wednesday of launching air attacks that sparked fires and damaged infrastructure just hours after their leaders agreed to a limited ceasefire to halt attacks on energy infrastructure.

Ukraine's air defence units shot down 72 of 145 drones launched by Russia in an overnight attack on Wednesday, the air force said. It said 56 drones were lost, in reference to the Ukrainian military using electronic warfare to redirect them.

Zelensky said that Russia launched more than 40 drones against Ukraine in the hours following the call between Trump and Putin. He urged the world to block any attempts by Moscow to drag out the war. “Russia is attacking civilian infrastructure and people - right now,” Andriy Yermak, Zelensky's chief of staff, said overnight on Telegram.

Moscow has launched devastating attacks on Ukraine's energy infrastructure throughout the war, while Ukraine has used drones to bomb multiple Russian oil installations.

Moscow also underlined that a fuller truce was dependent on its long-standing demands for a “complete cessation” of Western military and intelligence support to Ukraine's military.

Since seizing Crimea in 2014 and launching its full-scale invasion of Ukraine in February 2022, Moscow now occupies around a fifth of Ukraine.

(With inputs from agencies)