WASHINGTON—President Biden has for the first time authorized Ukrainian forces to use Western-made long-range weapons to strike inside Russia, allowing Kyiv to better defend itself against Russia, according to U.

President Volodymyr Zelensky on Sunday said "missiles will speak for themselves," following reports that U.S. President Joe Biden has authorized Ukraine to conduct strikes deeper into Russian territory.

Ukraine has been using the Army Tactical Missile System, more commonly known as ATACMS, on Russian targets in occupied Ukrainian territory for more than a year. It has used ATACMS to strike airbases in the occupied Crimean Peninsula and military positions in the Zaporizhzhia region.