Ukraine has the right under international law to attack military targets located in Russian territory, NATO Secretary General Jens Stoltenberg said during an interview on the United News telethon July 14.
United States policy prohibits Ukrainian forces from using U.S.-supplied weapons to strike targets deep within Russia. President Volodymyr Zelensky has called on Washington to lift restrictions, saying the ability to use long-range U.S. weapons such as ATACMS within Russia and occupied Crimea would produce “an instant result.”
In the interview, Stoltenberg affirmed Ukraine’s right to self-defense.
I suspect they mostly didn’t want their tech being examined by russia too easily, but at some point there will be so many scrap parts behind the front it doesn’t matter any more.