U.S. President Donald Trump has threatened to sue the BBC for at least $1 billion over its airing of what he says was a deceptively edited documentary, but the case could hinge on whether anyone in Florida watched it online and felt misled.

If that hurdle is cleared, a U.S. court would need to decide whether Britain's biggest broadcaster intentionally deceived viewers.

Here is a look at what Trump would need to prove and how the BBC could defend itself.

WHY DOES TRUMP WANT TO SUE THE BBC?

Trump and his lawyers have accused the BBC of defaming him by splicing together two parts of a January 6, 2021 speech to make it appear he directed his supporters to violently storm the U.S. Capitol.

In a letter viewed by Reuters, Trump's legal team gave the BBC until Friday to retract the October 2024 "Panorama" documentary news program episode where the excerpts appeared, or face a lawsuit seeking at least $1 billion.

Trump has denied inciting the riot.

Trump told Fox News host Laura Ingraham in an interview on Monday that he had an "obligation" to sue the BBC. "They defrauded the public and they've admitted it," he said.

BBC Chair Samir Shah has apologized for the editing of the footage and a BBC spokesperson said the broadcaster is reviewing the letter.

The revelation about the editing of Trump's speech and wider criticism of BBC News have plunged the broadcaster into crisis, resulting in the resignations of Director General Tim Davie and Chief Executive of News Deborah Turness on Sunday.

CAN TRUMP SUE THE BBC IN THE U.S.?

Trump's lawyers suggested in the letter that he would sue in Florida, where he has legal residency.

A threshold question would be whether the BBC has actively sought to establish a presence in Florida and whether people in the state watched the documentary and felt deceived by it, legal experts said.