The BBC engaged in a "serious breach" of broadcasting rules by not revealing that the narrator of a programme about the Gaza situation was the son of a Hamas official, according to British broadcasting authority Ofcom.
An inquiry by the media regulator into Gaza: How to Survive a Warzone has determined that the film was "substantially inaccurate".
The chief executive of the broadcaster had previously apologised, noting there had been "a major oversight in relation to accuracy".
The regulator has directed the broadcaster to air a evening announcement about its conclusions.
"Since this amounts to a major infringement of our code, we are directing the corporation to broadcast a announcement of our determinations against it on the BBC's second channel at 21:00, with a date to be determined," the regulator stated.
'Possibility to Damage Trust'
The authority's statement said: "Our investigation concluded that the film's lack of disclosure that the voice's parent served in a position in the Hamas-administered government was significantly deceptive.
"It meant that the public did not have essential details which may have been highly relevant to their assessment of the presenter and the details he shared.
"Credibility is at the heart of the bond between a broadcaster and its viewers, notably for a national broadcasting corporation such as the BBC.
"This oversight had the risk to erode the significantly high levels of trust that viewers would have placed in a BBC factual programme about the conflict in Gaza."
The documentary was removed from iPlayer in the month of February after the presenter's personal associations came to light, and in July an internal BBC review concluded it violated the broadcaster's editorial guidelines on factual correctness.
A BBC spokesperson commented: "The regulator's decision is in accordance with the findings of the corporation's inquiry, that there was a major oversight in the documentary in relation to the corporation's content standards on truthfulness, which corresponds to Rule 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we agree with the authority's determination in full. We will comply with the sanction as soon as the timing and wording are determined."
