Donald Trump has threatened to sue the BBC for $1billion over the editing of a 2021 speech broadcast by Panorama.
BBC chairman Samir Shah stated there is "no basis for a defamation case" and the corporation is "determined to fight this" to protect licence fee payers.
The BBC apologised for the editing, which gave the "mistaken impression that Mr Trump had made a direct call for violent action," but refused to pay financial compensation.
The Panorama scandal led to the resignations of two senior BBC executives, director-general Tim Davie and news chief Deborah Turness.
Despite speculation, Sir Keir Starmer did not speak to Mr Trump over the weekend regarding the issue, with the Prime Minister's office stating it is a matter for the independent BBC.