Russia used at least 430 drones and 18 missiles in the nighttime attack, Ukrainian President Volodymyr Zelensky said.

Russian President Vladimir Putin “has put us on notice that we need to quickly build those steps of the ladder of the defense of our outer perimeter,” Poland's foreign minister said.

The wall is intended to protect cities and key infrastructure from Russian glide bombs and Shahed-type drones.

Britain and Belgium aren't blaming anyone for the mystery drones, but they're the latest in a series of airspace violations one NATO ally calls Russian "hybrid warfare."

Russian drone strikes hit Kharkiv early Wednesday morning, injuring five people, according to local officials.

An automated machine gun turret made by UGV Robotics for Ukrainian naval drones is pivoting to a new mission on land.

Elsewhere, the president of Finland warned that a ceasefire in Ukraine is unlikely before the spring and urged European allies to keep up support.

Belgium has enlisted the help of foreign armed forces to seize or track down drones that have made incursions around its airports, military bases and a nuclear plant, with officials saying it all bears the hallmarks of Russian interference.