What are the latest developments in the Ukraine conflict, particularly regarding the Chernobyl drone strike and U.S. diplomatic efforts?

Ukraine reports that a Russian drone strike caused significant damage to the protective shelter at Chernobyl nuclear site, though radiation levels remain stable. Ukrainian officials view this attack as evidence that Putin isn't genuinely interested in negotiations but rather in deceiving the international community. Russia's spokesperson Dmitry Peskov has denied responsibility, claiming the incident was staged by Ukraine. Meanwhile, diplomatic efforts are intensifying with an unscheduled meeting between Vice President Vance and President Zelensky. The U.S. position reportedly includes expectations that Ukraine must cede territory to end the conflict, a stance that has frustrated NATO allies. Critics, including Estonia's former president, argue that such concessions effectively hand Ukraine to Russia before negotiations even begin.