The BBC committed a "serious breach" of industry standards by omitting to mention that the voice of a film about Gaza was the offspring of a Hamas representative, according to regulatory body Ofcom.
An inquiry by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has concluded that the film was "materially misleading".
The chief executive of the broadcaster had previously apologised, saying there had been "a major oversight in relation to factual correctness".
The authority has ordered the BBC to transmit a evening declaration about its decisions.
"Given this constitutes a significant violation of our regulations, we are ordering the BBC to broadcast a statement of our findings against it on the BBC's second channel at 21:00, with a timing to be finalised," the statement read.
'Potential to Damage Confidence'
The authority's announcement declared: "Our investigation determined that the documentary's lack of disclosure that the voice's father held a position in the Hamas-run administration was materially misleading.
"Consequently that the viewers did not have critical information which may have been highly relevant to their judgment of the presenter and the content he shared.
"Trust is at the heart of the connection between a broadcaster and its public, notably for a national broadcasting corporation such as the public broadcaster.
"This oversight had the risk to damage the very considerable levels of credibility that viewers would have placed in a factual film from the broadcaster about the conflict in Gaza."
The film was withdrawn from iPlayer in the month of February after the narrator's personal associations came to light, and in July an internal BBC review concluded it breached the broadcaster's journalistic standards on accuracy.
A representative for the broadcaster commented: "The Ofcom ruling is in line with the findings of the corporation's inquiry, that there was a serious error in the documentary in relation to the broadcaster's journalistic policies on accuracy, which aligns with clause 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we comply with the regulator's ruling in its entirety. We will follow the directive as soon as the schedule and wording are finalised."
