The British broadcaster was found to have committed a "significant breach" of broadcasting rules by not revealing that the narrator of a film about the Gaza situation was the offspring of a Hamas administrator, as determined by regulatory body Ofcom.
An inquiry by Ofcom into Gaza: How to Survive a Warzone has determined that the documentary was "materially misleading".
The chief executive of the broadcaster had earlier expressed regret, saying there had been "a major oversight in relation to truthfulness".
Ofcom has instructed the BBC to broadcast a evening announcement about its conclusions.
"Given this constitutes a serious breach of our regulations, we are ordering the corporation to transmit a announcement of our findings against it on BBC2 at 9pm, with a timing to be confirmed," the regulator stated.
'Possibility to Erode Confidence'
The regulator's statement stated: "Our investigation found that the programme's failure to disclose that the narrator's parent held a role in the Hamas-administered administration was significantly deceptive.
"Consequently that the audience did not have vital facts which may have been extremely pertinent to their evaluation of the presenter and the content he shared.
"Trust is at the core of the connection between a broadcaster and its public, especially for a state-funded media outlet such as the BBC.
"This failing had the potential to damage the significantly high amounts of trust that the public would have invested in a documentary produced by the BBC about the conflict in Gaza."
The film was removed from the online platform in the month of February after the presenter's personal associations were revealed, and in July an broadcaster's internal assessment concluded it violated the corporation's content policies on factual correctness.
A BBC spokesperson commented: "The authority's determination is in accordance with the results of Peter Johnston's review, that there was a significant failing in the documentary in relation to the broadcaster's journalistic policies on factual correctness, which reflects clause 2.2 of the authority's broadcasting regulations.
"We expressed regret for this and we accept the authority's determination in full. We will adhere to the sanction as soon as the timing and wording are determined."
