With one surprise attack after another, Ukraine keeps inventing new ways to wage war with drones. In turn, Russia is building a massive drone army of its own.

President Trump said the Russian leader Vladimir Putin had warned that he would retaliate for a covert Ukrainian attack in Russia last weekend that destroyed dozens of Russian bombers.

Russia has proposed another attempt at peace negotiations with Ukraine on Monday in Istanbul, but both sides remain firmly entrenched in positions likely to prolong the war.

NPR visits a hospital in eastern Ukraine's Donetsk region, in a town where many residents have fled but some young couples are holding on and hoping to raise their children one day in peace.

At least 12 people were killed and dozens injured in strikes that hit more than 30 cities and villages across Ukraine.

Ukraine and Russia have begun the exchange of 1,000 prisoners of war, the largest such swap since the beginning of Russia's full-scale invasion of Ukraine in February 2022.

President Trump is working the phones on Monday, holding calls with the leaders of Russia, Ukraine and other European countries as he continues efforts to negotiate an end to the war in Ukraine.

President Trump said he plans to speak by phone with Russian leader Vladimir Putin, followed by Ukrainian President Volodymyr Zelenskyy and leaders of NATO countries, about ending the war in Ukraine.

Ukrainian President Volodymyr Zelenskyy is in Turkey for direct talks with Russia. But the Kremlin sent a lower-level delegation that doesn't include President Vladimir Putin.

There are lots of unknowns ahead of potential direct talks between Russia and Ukraine in Turkey.

The two countries have agreed to a deal to jointly invest in Ukraine's mineral, raw materials and natural resource wealth in exchange for future U.S. aid.

Russia declared a three-day ceasefire in Ukraine starting May 8 for the anniversary of the Soviet Union's victory over Nazi Germany. Ukraine called for an immediate, 30-day truce instead.

Ukrainians displaced by Russian occupation are helping the war effort — and longing for the homes they fled and the loved ones they left behind.

It was their first face-to-face meeting since they argued in front of cameras in the Oval Office in February — and comes as efforts intensify to end Russia's war in Ukraine.

Trump calls on Putin to stop attacks as Ukrainian military says Russia launched at least 215 drones and missiles at Ukraine, most aimed at the capital.