The British broadcaster committed a "significant breach" of media regulations by not revealing that the presenter of a programme about the Gaza situation was the offspring of a Hamas administrator, as determined by regulatory body Ofcom.
An inquiry by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has determined that the film was "significantly deceptive".
The BBC's director general had previously apologised, noting there had been "a serious error in relation to accuracy".
The regulator has ordered the BBC to transmit a peak-time declaration about its decisions.
"Given this constitutes a significant violation of our code, we are instructing the BBC to transmit a message of our determinations against it on BBC Two at 21:00, with a timing to be confirmed," it said.
'Potential to Erode Confidence'
The authority's report declared: "Our investigation determined that the documentary's failure to disclose that the presenter's male guardian served in a position in the Hamas-run administration was substantially inaccurate.
"It meant that the audience did not have essential details which may have been highly relevant to their evaluation of the voice and the content he provided.
"Trust is at the center of the bond between a broadcaster and its public, particularly for a public service broadcaster such as the BBC.
"This failing had the potential to damage the significantly high amounts of credibility that the public would have placed in a factual film from the broadcaster about the conflict in Gaza."
The programme was removed from iPlayer in February after the narrator's personal associations were revealed, and in the month of July an broadcaster's internal assessment concluded it infringed the organization's editorial guidelines on accuracy.
A corporation official commented: "The Ofcom ruling is in line with the results of Peter Johnston's review, that there was a serious error in the film in relation to the broadcaster's journalistic policies on factual correctness, which reflects clause 2.2 of the regulator's media standards.
"We issued an apology for this and we agree with the regulator's ruling in its entirety. We will adhere to the penalty as soon as the date and wording are confirmed."
