The BBC was found to have committed a "serious breach" of broadcasting rules by omitting to mention that the narrator of a film about Gaza was the child of a Hamas administrator, as determined by British broadcasting authority Ofcom.
An probe by Ofcom into Gaza: How to Survive a Warzone has concluded that the programme was "substantially inaccurate".
The BBC's director general had earlier expressed regret, saying there had been "a major oversight in relation to accuracy".
Ofcom has ordered the broadcaster to broadcast a evening declaration about its conclusions.
"As this represents a significant violation of our rules, we are ordering the BBC to air a message of our conclusions against it on BBC Two at 21:00, with a date to be determined," the statement read.
'Risk to Damage Credibility'
The watchdog's statement stated: "Our investigation determined that the programme's failure to disclose that the presenter's father held a post in the Hamas-controlled authority was materially misleading.
"Consequently that the public did not have critical information which may have been highly relevant to their judgment of the presenter and the content he presented.
"Confidence is at the heart of the relationship between a television network and its audience, especially for a public service broadcaster such as the public broadcaster.
"This error had the potential to damage the significantly high degrees of trust that viewers would have placed in a factual film from the broadcaster about the Israel-Gaza war."
The programme was removed from the online platform in the month of February after the narrator's personal associations were revealed, and in this past July an corporation's own inquiry concluded it breached the broadcaster's editorial guidelines on accuracy.
A representative for the broadcaster stated: "The authority's determination is in agreement with the conclusions of the internal assessment, that there was a significant failing in the film in relation to the BBC's Editorial Guidelines on accuracy, which corresponds to clause 2.2 of the regulator's media standards.
"We have apologised for this and we accept the regulator's ruling in complete. We will follow the penalty as soon as the date and wording are finalised."
