Ukrainian President Volodymyr Zelenskyy said Wednesday it is vital to bolster his country’s air defenses and speed delivery of F-16 fighter jets for use against Russia’s invasion.

“There are no rational explanations for why Patriots, which are plentiful around the world, are still not covering the skies of Kharkiv and other cities and communities under attack by Russian terrorists,” Zelenskyy said on social media. “Every day, we work to provide better protection for our people and Ukraine.”

Zelenskyy’s comments came after Russian strikes on the eastern Ukrainian city of Kharkiv killed one person and injured 19 others.

Kharkiv Mayor Ihor Terekhov said the Russian attack damaged 18 residential buildings.

Russia said Wednesday it thwarted rocket attacks by Ukraine targeting the Belgorod region, while Ukraine said Russia attacked overnight with 13 aerial drones.

Russia’s Defense Ministry said the country’s air defenses shot down 18 Ukrainian rockets.

Vyacheslav Gladkov, the governor of Belgorod, said on Telegram there was some damage to homes in several villages, and that at least one person was hurt.

Belgorod, located along the border between Russia and Ukraine, is a frequent target of Ukrainian attacks as Ukraine seeks to defeat the invasion Russia launched more than two years ago.

Some information for this report came from Reuters.