The BBC engaged in a "serious breach" of media regulations by failing to disclose that the presenter of a film about the Gaza conflict was the offspring of a Hamas official, as ruled by UK media regulator Ofcom.
An investigation by the media regulator into the programme Gaza: How to Survive a Warzone has found that the film was "materially misleading".
The head of the BBC had already issued an apology, noting there had been "a significant failing in relation to truthfulness".
The authority has instructed the BBC to air a evening statement about its conclusions.
"Given this constitutes a serious breach of our rules, we are directing the BBC to transmit a message of our conclusions against it on BBC2 at nine o'clock in the evening, with a timing to be finalised," the regulator stated.
'Potential to Damage Trust'
The regulator's statement said: "The inquiry we conducted found that the documentary's omission to reveal that the voice's parent occupied a post in the Hamas-run administration was significantly deceptive.
"It meant that the audience did not have critical information which may have been very significant to their judgment of the voice and the content he provided.
"Confidence is at the center of the relationship between a television network and its viewers, especially for a state-funded media outlet such as the British Broadcasting Corporation.
"This error had the possibility to undermine the significantly high amounts of trust that viewers would have placed in a factual film from the broadcaster about the conflict in Gaza."
The programme was pulled from the BBC's streaming service in February after the narrator's familial connections came to light, and in the month of July an corporation's own inquiry concluded it infringed the organization's content policies on factual correctness.
A BBC spokesperson said: "The regulator's decision is in line with the results of the corporation's inquiry, that there was a significant failing in the film in relation to the broadcaster's journalistic policies on factual correctness, which corresponds to clause 2.2 of Ofcom's Broadcasting Code.
"We issued an apology for this and we agree with the authority's determination in full. We will comply with the penalty as soon as the date and language are confirmed."
