The BBC was found to have committed a "serious breach" of industry standards by omitting to mention that the voice of a film about the Gaza conflict was the child of a Hamas official, according to UK media regulator Ofcom.
An investigation by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has found that the documentary was "substantially inaccurate".
The BBC's director general had previously apologised, saying there had been "a significant failing in relation to accuracy".
The regulator has instructed the broadcaster to transmit a peak-time announcement about its decisions.
"As this represents a major infringement of our code, we are instructing the BBC to transmit a statement of our conclusions against it on BBC Two at 21:00, with a date to be determined," the regulator stated.
'Risk to Undermine Confidence'
The watchdog's report stated: "The inquiry we conducted concluded that the documentary's failure to disclose that the voice's parent occupied a post in the Hamas-run authority was significantly deceptive.
"This implied that the viewers did not have essential details which may have been very significant to their evaluation of the voice and the details he shared.
"Credibility is at the heart of the bond between a broadcaster and its audience, especially for a public service broadcaster such as the British Broadcasting Corporation.
"This oversight had the possibility to undermine the exceptionally strong levels of trust that audiences would have placed in a factual film from the broadcaster about the conflict in Gaza."
The documentary was withdrawn from iPlayer in February after the narrator's personal associations came to light, and in July an broadcaster's internal assessment concluded it infringed the broadcaster's journalistic standards on truthfulness.
A representative for the broadcaster stated: "The regulator's decision is in line with the conclusions of the internal assessment, that there was a major oversight in the documentary in relation to the broadcaster's journalistic policies on factual correctness, which aligns with clause 2.2 of the regulator's media standards.
"We have apologised for this and we accept the authority's determination in its entirety. We will comply with the directive as soon as the timing and wording are finalised."
