Biden then met on May 17 with Blinken, who visited Kyiv earlier this month to take stock of the grave situation created by Russia’s move towards Kharkiv, and was widely reported to be pressing Biden to relax the rules.
After working out the details, the US President gave it final approval in recent days, but the decision was kept secret for operational reasons and it came into effect only on Thursday.
However, the White House has made it clear to Kiev that permission for cross-border strikes is limited to cross-border targets, and those being used by Russia to launch an invasion.
Officials also stressed that they had expected some form of Russian invasion, and that the arrival of American weapons had averted this, preventing a possible capture of the city of Kharkiv.