US President Joe Biden has authorized Ukraine to use US-supplied weapons to attack targets in Russia, but only near the Kharkiv region, US officials say.
One told BBC News that his team had been instructed to ensure that Ukraine uses US weapons “for hostile purposes” to “attack Russian forces or attack them in return”.
While Washington’s policy of not allowing long-range strikes into Russia remains unchanged, Moscow will consider the latest move an escalation.
Russian forces have made gains in recent weeks in the Kharkiv region after a surprise offensive in the area near the border with Russia.
A US official told the BBC: “Our policy has not changed on banning the use of ATACMS or long-range strikes inside Russia.”
Asked by the BBC’s American partner CBS if the new policy included striking Russian aircraft, one official said: “We never told them. [Ukraine] They cannot shoot down a Russian plane on Russian soil that is coming to attack them.
The White House and State Department had no immediate comment.
Britain has previously signaled it is open to loosening restrictions on how Ukraine can use Western-supplied weapons.
Despite concerns that such a development could further escalate the conflict, several European leaders have recently called for a loosening of restrictions on the use of such weapons.
But Washington, which supplies most of Ukraine’s arms, has resisted easing these restrictions because of fears of escalation.
US Secretary of State Anthony Blinken hinted at the change during a visit to Moldova on Wednesday.
“Every step of the way, we’ve adapted and adjusted as needed,” he said.
“So that’s what we’ll be doing going forward.”
Russian forces appear to have seized the opportunity recently to push deeper into Ukrainian territory in Kharkiv, while Kiev waited for more Western arms to arrive.