Russia has vowed to destroy all fighter jets donated to Ukraine by European nations after Poland and Slovakia, backed by new equipment and finance from the U.S. and the European Union, became the first countries to send warplanes to Kyiv.

Fighter jets have been a long-term demand for the Ukrainian government of Volodymyr Zelensky since the renewed Russian invasion at the start of 2022, but NATO leaders have shied away from what they considered a major escalation of their involvement in the conflict until now. Enabled by cash and replacement warbirds from the United States and the European Union, two European nations are sending fighter jets to Ukraine in the coming days.