The decision by President Biden will allow Ukraine to fire into Russia using US long-range missiles it's had for more than a year.

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.

These Army Tactical Missile System (ATACMS) are only authorized for use in the Kursk area, a source with knowledge of the issue said.