The BBC committed a "serious breach" of media regulations by omitting to mention that the voice of a programme about Gaza was the child of a Hamas official, according to UK media regulator Ofcom.
An probe by Ofcom into the programme Gaza: How to Survive a Warzone has concluded that the programme was "substantially inaccurate".
The head of the BBC had already issued an apology, saying there had been "a significant failing in relation to truthfulness".
Ofcom has ordered the broadcaster to broadcast a peak-time statement about its findings.
"As this represents a major infringement of our rules, we are instructing the broadcaster to transmit a statement of our determinations against it on BBC2 at 21:00, with a date to be confirmed," it said.
'Potential to Erode Trust'
The watchdog's statement stated: "Our probe determined that the documentary's omission to reveal that the voice's male guardian occupied a role in the Hamas-controlled government was materially misleading.
"Consequently that the viewers did not have critical information which may have been highly relevant to their assessment of the presenter and the information he shared.
"Credibility is at the core of the relationship between a television network and its audience, particularly for a public service broadcaster such as the BBC.
"This error had the possibility to erode the very considerable levels of trust that audiences would have placed in a BBC factual programme about the conflict in Gaza."
The film was pulled from the online platform in last February after the presenter's familial connections were revealed, and in this past July an corporation's own inquiry determined it violated the corporation's journalistic standards on truthfulness.
A corporation official stated: "The regulator's decision is in agreement with the conclusions of the corporation's inquiry, that there was a major oversight in the programme in relation to the corporation's content standards on accuracy, which corresponds to clause 2.2 of the regulator's media standards.
"We expressed regret for this and we accept the authority's determination in complete. We will adhere to the sanction as soon as the schedule and language are finalised."
