UK politicians have urged Prime Minister Keir Starmer to publicly defend the BBC after Donald Trump filed a lawsuit seeking up to $10bn (£7.9bn) from the broadcaster over an edited clip used in a Panorama documentary.

The claim, filed in the US District Court for the Southern District of Florida, alleges the BBC “intentionally, maliciously and deceptively” manipulated footage of Trump’s 6 January 2021 speech in order to portray him as inciting violence and to influence the 2024 US presidential election. The BBC has previously apologised for the edit and said it would not rebroadcast the programme, but has rejected suggestions it has a viable defamation case to answer.

Ed Davey, the Liberal Democrat leader, said Starmer should “stand up for the BBC” and make clear Trump’s legal threat was “unacceptable”. Davey argued that a demand of this scale risked intimidating the UK’s public service broadcaster and, ultimately, leaving licence fee payers exposed to the costs of fighting the case or any settlement.

The pressure comes as ministers are due to publish a green paper setting out options for the BBC’s future funding and charter renewal into the 2030s, adding to a day of heightened political attention on the corporation’s independence and governance.

The lawsuit centres on the Panorama programme “Trump: A Second Chance?”, broadcast in the UK on 28 October 2024. Trump’s lawyers allege the documentary spliced together two non-contiguous parts of his speech, almost an hour apart, to make it appear he issued a single, continuous call for supporters to march to the US Capitol and “fight like hell”. The claim also alleges the BBC removed nearby language in which Trump said supporters should protest “peacefully” and “patriotically”.

Trump is seeking $5bn in damages for defamation and a further $5bn under Florida’s Deceptive and Unfair Trade Practices Act. The complaint argues the Florida court has jurisdiction because the BBC conducts business in the state through its website and the BritBox streaming service, and because US viewers could access BBC content online. BBC One and iPlayer are not available in the US.

A health minister, Stephen Kinnock, signalled government support for the corporation’s stance, saying BBC leaders were “right to stick by their guns” against Trump’s wider allegations. Kinnock said Labour would “always stand up for the BBC”, while maintaining the broadcaster’s operational independence from government.

The dispute has already triggered debate over whether the BBC should fight the case in court or seek a settlement to limit costs and disclosure. Christopher Ruddy, the chief executive of Newsmax and a Trump ally, said on BBC Radio 4’s Today programme that the action could ultimately settle for about $10m, far below the $10bn sought in the complaint. Ruddy said US litigation could become “ugly”, suggesting a long legal battle would be expensive and could expose internal BBC communications during the disclosure process. He estimated the BBC’s costs could reach $50m to $100m if the case ran its course.

Mark Damazer, a former senior BBC executive and a former controller of Radio 4, took the opposite view, also speaking on Today. He said the BBC “should definitely fight”, arguing it would be more damaging to the corporation’s reputation to appear to cave in to political pressure than to contest the allegations in court.

Legal experts have noted that, as a public figure, Trump would face a high bar under US defamation law, needing to show “actual malice” — that the BBC published information knowing it was false or with reckless disregard for the truth — a standard established by the US Supreme Court in New York Times v Sullivan. The BBC has said the edit was a mistake made in the course of shortening a long speech, rather than an attempt to mislead.

The corporation’s handling of the Panorama clip has already led to serious internal fallout. In November, the BBC issued an apology to Trump, with BBC chair Samir Shah writing personally to the White House, and the broadcaster said it would not rebroadcast the documentary. The row fed into a wider crisis over editorial standards which culminated in the resignations of director general Tim Davie and the head of BBC News, Deborah Turness.

Trump’s complaint also quotes criticism of the BBC by senior Conservatives, including party leader Kemi Badenoch and former prime minister Liz Truss, who have accused the corporation of bias and “fake news”. Their remarks are cited in the US filing as purported support for the claim that the BBC acted with malice.

Downing Street has not set out a detailed position on the lawsuit beyond stressing the BBC’s independence. Opposition parties and former BBC figures are now calling for a more explicit public defence, arguing the case has become a test of political support for the UK’s public broadcaster amid what they describe as a growing international campaign to discredit mainstream media.