The public service broadcaster engaged in a "major breach" of broadcasting rules by omitting to mention that the voice of a documentary about Gaza was the offspring of a Hamas administrator, as ruled by UK media regulator Ofcom.
An inquiry by Ofcom into the documentary titled Gaza: How to Survive a Warzone has determined that the programme was "substantially inaccurate".
The BBC's director general had earlier expressed regret, saying there had been "a serious error in relation to factual correctness".
The regulator has instructed the corporation to air a peak-time declaration about its decisions.
"As this represents a serious breach of our code, we are directing the BBC to transmit a statement of our determinations against it on BBC Two at 21:00, with a date to be finalised," it said.
'Possibility to Erode Trust'
The watchdog's report said: "Our probe concluded that the film's failure to disclose that the presenter's parent served in a role in the Hamas-administered authority was significantly deceptive.
"This implied that the audience did not have essential details which may have been extremely pertinent to their evaluation of the voice and the content he provided.
"Credibility is at the core of the connection between a television network and its public, notably for a national broadcasting corporation such as the British Broadcasting Corporation.
"This oversight had the possibility to damage the significantly high levels of trust that the public would have invested in a factual film from the broadcaster about the Gaza conflict."
The documentary was withdrawn from iPlayer in February after the narrator's family links emerged, and in July an broadcaster's internal assessment determined it infringed the organization's content policies on factual correctness.
A BBC spokesperson commented: "The regulator's decision is in accordance with the conclusions of the internal assessment, that there was a significant failing in the programme in relation to the corporation's content standards on truthfulness, which corresponds to clause 2.2 of the regulator's media standards.
"We issued an apology for this and we comply with the authority's determination in full. We will follow the sanction as soon as the date and wording are confirmed."
