Donald Trump has won a partial legal victory after a federal judge allowed his $10 billion defamation lawsuit against the BBC to proceed, rejecting a bid by the British broadcaster to have the case dismissed. The president hailed the ruling on Truth Social as "A Huge Victory".

US District Judge Jeffrey T. Kuntz in Florida ruled on Tuesday that Trump's defamation claim could go forward, but threw out a separate claim brought under Florida's consumer protection law. Trump is suing the BBC for at least $10 billion over a misleadingly edited clip of a speech that, he says, made it appear he directed supporters to storm the US Capitol on 6 January 2021.

The dispute centres on a BBC Panorama documentary that spliced together parts of Trump's speech to supporters on the day of the Capitol riot. The lawsuit, filed in December in a Florida federal court, accuses the BBC of defaming him by joining a section in which he told supporters to march on the Capitol with another in which he used fighting language, creating the impression that he had urged them to storm the building.

Judge Kuntz declined to throw out the defamation claim, saying Trump had plausibly alleged that the broadcaster damaged his reputation and knew, or should have known, that the clip was misleading. The ruling does not decide the case: it means only that the lawsuit survives the BBC's attempt to end it at the earliest stage, and that the broadcaster must now defend the claim in court.

The BBC had asked the judge to dismiss the case entirely. Its failure to do so is a setback for the broadcaster, which is publicly funded and has faced intense scrutiny over the editing of the documentary. The ruling leaves the BBC exposed to a claim that could, in theory, run into billions of dollars, although damages of that scale are rarely awarded in defamation cases and the broadcaster is expected to fight the claim vigorously.

Trump has sought at least $5 billion for the defamation claim and a further $5 billion for the consumer protection claim that has now been dismissed. The case is one of several Trump has filed against news organisations as part of a wider pressure campaign against coverage he dislikes, and it is being watched closely by media lawyers on both sides of the Atlantic.

The ruling is not the first twist in the case. Last month, the president faced a setback when a magistrate judge ordered him to give a deposition by 11 December, after the BBC claimed he was dodging its efforts to take sworn testimony from him. That order stands, and Trump will now have to sit for questioning under oath as the case moves forward.

For the BBC, the case has already proved costly in reputational terms. The editing of the Panorama programme has been the subject of fierce criticism in Britain, where the broadcaster's impartiality and editorial standards are under constant political scrutiny. A court case in Florida, with the prospect of a sitting US president giving evidence about his own speech, is the last thing its executives would have wanted.

The legal arguments ahead are likely to turn on what the BBC knew when the programme was broadcast, and on whether the editing amounted to the kind of reckless disregard for the truth that American defamation law requires when the claimant is a public figure. Trump will have to show not merely that the clip was misleading, but that the BBC acted with actual malice — a high bar that has protected American news organisations in many past cases.

The BBC has not yet said whether it will appeal the ruling or seek to have the case moved or narrowed further. Its lawyers are likely to argue that the documentary was fair comment on a matter of overwhelming public interest, and that the editing, while clumsy, did not change the substance of what Trump said that day.

Whatever happens next, the ruling guarantees that the case will continue to hang over the BBC for months, and that the president's long-running confrontation with the broadcaster will now play out in a Florida courtroom rather than on social media. The next milestone is Trump's deposition in December, after which both sides will set out their evidence in detail.