The British broadcaster engaged in a "major breach" of industry standards by failing to disclose that the voice of a documentary about Gaza was the child of a Hamas official, as determined by UK media regulator Ofcom.
An investigation by Ofcom into Gaza: How to Survive a Warzone has determined that the programme was "materially misleading".
The head of the BBC had earlier expressed regret, saying there had been "a major oversight in relation to accuracy".
The authority has instructed the broadcaster to broadcast a evening declaration about its conclusions.
"As this represents a major infringement of our rules, we are instructing the corporation to air a announcement of our findings against it on the BBC's second channel at 21:00, with a date to be determined," it said.
'Risk to Damage Trust'
The authority's statement declared: "Our probe found that the programme's omission to reveal that the narrator's parent occupied a post in the Hamas-administered administration was materially misleading.
"This implied that the audience did not have vital facts which may have been highly relevant to their evaluation of the presenter and the content he provided.
"Confidence is at the heart of the relationship between a broadcaster and its viewers, particularly for a national broadcasting corporation such as the BBC.
"This error had the potential to erode the exceptionally strong levels of trust that the public would have invested in a factual film from the broadcaster about the Gaza conflict."
The documentary was removed from the online platform in February after the presenter's family links were revealed, and in this past July an corporation's own inquiry determined it infringed the broadcaster's editorial guidelines on truthfulness.
A BBC spokesperson stated: "The regulator's decision is in accordance with the results of the internal assessment, that there was a major oversight in the programme in relation to the corporation's content standards on truthfulness, which corresponds to clause 2.2 of the authority's broadcasting regulations.
"We issued an apology for this and we agree with Ofcom's decision in full. We will follow the sanction as soon as the schedule and wording are confirmed."
