Joe Biden has given the green light for the US-made weapon to be used inside Russia. How will it affect the war?

Joe Biden has permitted Ukraine to use US-made Atacms ballistic missiles against Russian and North Korean forces inside Russian territory.

Officials in Washington told reporters the weapons could be used in the region of Kursk, where Kyiv has launched an incursion, but that that US president may agree to their deployment elsewhere before Donald Trump comes to power.