US weapons were used to attack Russian territory
US National Security Adviser Jake Sullivan confirmed that US weapons were used to attack Russian territory.
“So the president authorized that. The Ukrainians exercised that right on the battlefield,” Sullivan said in an interview with CBS.
“What I'm just saying is, from the president's perspective, this is common sense,” he added.

US Secretary of State Antony Blinken confirmed on May 31 that President Biden had authorized the use of US weapons to strike Russian territory. According to him, these weapons can only be used to strike Russian areas near Kharkiv. Blinken did not rule out the possibility of expanding the range in the future.
Meanwhile, the German cabinet of ministers stated that German weapons could be used to protect the Kharkiv region from Russian attacks. Currently, there is no consensus among Western countries on restrictions on the weapons they supply to Ukraine.
Russian President Vladimir Putin said on May 28 that the selection of targets and flight missions for modern strike systems is carried out remotely or automatically, "without the presence of Ukrainian servicemen." He pointed out that this is done by those who produce and supply these systems to Ukraine. Putin warned that NATO countries should "realize what they are playing with."
Russian Security Council Deputy Chairman Dmitry Medvedev stressed on May 31 that all long-range weapons delivered to Ukraine were “under direct control of NATO servicemen” and such actions could serve as a pretext for retaliatory strikes./.