The BBC was found to have committed a "major breach" of industry standards by not revealing that the narrator of a programme about the Gaza situation was the offspring of a Hamas administrator, as determined by British broadcasting authority Ofcom.
An probe by the media regulator into the documentary titled Gaza: How to Survive a Warzone has found that the programme was "substantially inaccurate".
The chief executive of the broadcaster had earlier expressed regret, stating there had been "a major oversight in relation to factual correctness".
The authority has ordered the BBC to broadcast a peak-time announcement about its findings.
"As this represents a serious breach of our regulations, we are ordering the BBC to air a message of our findings against it on BBC2 at 21:00, with a schedule to be confirmed," the statement read.
'Risk to Erode Trust'
The regulator's announcement stated: "Our investigation determined that the film's lack of disclosure that the narrator's male guardian held a role in the Hamas-administered administration was significantly deceptive.
"Consequently that the audience did not have critical information which may have been very significant to their assessment of the narrator and the information he provided.
"Confidence is at the heart of the bond between a television network and its public, particularly for a state-funded media outlet such as the public broadcaster.
"This error had the possibility to erode the significantly high levels of confidence that audiences would have put in a factual film from the broadcaster about the conflict in Gaza."
The programme was removed from the BBC's streaming service in the month of February after the narrator's familial connections were revealed, and in the month of July an internal BBC review concluded it infringed the organization's journalistic standards on factual correctness.
A BBC spokesperson stated: "The authority's determination is in accordance with the findings of the internal assessment, that there was a serious error in the film in relation to the corporation's content standards on accuracy, which aligns with clause 2.2 of the authority's broadcasting regulations.
"We issued an apology for this and we accept the regulator's ruling in complete. We will follow the penalty as soon as the timing and wording are confirmed."
