The public service broadcaster committed a "serious breach" of broadcasting rules by omitting to mention that the presenter of a documentary about the Gaza situation was the child of a Hamas administrator, according to regulatory body Ofcom.
An investigation by the broadcasting watchdog into Gaza: How to Survive a Warzone has found that the documentary was "significantly deceptive".
The BBC's director general had previously apologised, stating there had been "a major oversight in relation to factual correctness".
The regulator has ordered the broadcaster to air a evening declaration about its conclusions.
"As this represents a serious breach of our regulations, we are ordering the corporation to air a message of our findings against it on the BBC's second channel at 21:00, with a schedule to be determined," it said.
'Risk to Damage Trust'
The watchdog's report stated: "Our investigation concluded that the documentary's lack of disclosure that the narrator's male guardian occupied a post in the Hamas-run government was materially misleading.
"Consequently that the audience did not have critical information which may have been extremely pertinent to their assessment of the presenter and the details he provided.
"Trust is at the core of the connection between a television network and its viewers, particularly for a public service broadcaster such as the public broadcaster.
"This oversight had the possibility to erode the very considerable amounts of trust that audiences would have invested in a documentary produced by the BBC about the Israel-Gaza war."
The film was withdrawn from iPlayer in February after the presenter's personal associations were revealed, and in this past July an broadcaster's internal assessment determined it breached the organization's content policies on accuracy.
A representative for the broadcaster stated: "The Ofcom ruling is in agreement with the conclusions of Peter Johnston's review, that there was a serious error in the documentary in relation to the broadcaster's journalistic policies on accuracy, which corresponds to clause 2.2 of Ofcom's Broadcasting Code.
"We expressed regret for this and we comply with the regulator's ruling in complete. We will comply with the penalty as soon as the schedule and wording are determined."
