The public service broadcaster was found to have committed a "serious breach" of broadcasting rules by not revealing that the voice of a programme about the Gaza conflict was the child of a Hamas representative, as determined by British broadcasting authority Ofcom.
An probe by the media regulator into Gaza: How to Survive a Warzone has concluded that the documentary was "substantially inaccurate".
The head of the BBC had earlier expressed regret, noting there had been "a major oversight in relation to accuracy".
Ofcom has directed the corporation to broadcast a evening announcement about its findings.
"Since this amounts to a serious breach of our code, we are ordering the BBC to air a announcement of our determinations against it on BBC2 at 21:00, with a timing to be finalised," the regulator stated.
'Possibility to Undermine Confidence'
The regulator's statement said: "Our investigation found that the programme's lack of disclosure that the narrator's father served in a position in the Hamas-run government was materially misleading.
"This implied that the audience did not have critical information which may have been highly relevant to their assessment of the presenter and the details he provided.
"Confidence is at the core of the connection between a broadcaster and its viewers, notably for a state-funded media outlet such as the BBC.
"This oversight had the possibility to undermine the significantly high degrees of credibility that audiences would have invested in a BBC factual programme about the Gaza conflict."
The documentary was pulled from the online platform in February after the narrator's familial connections came to light, and in July an broadcaster's internal assessment concluded it breached the corporation's content policies on factual correctness.
A BBC spokesperson stated: "The regulator's decision is in accordance with the conclusions of Peter Johnston's review, that there was a significant failing in the documentary in relation to the BBC's Editorial Guidelines on factual correctness, which aligns with clause 2.2 of the regulator's media standards.
"We issued an apology for this and we comply with Ofcom's decision in full. We will comply with the sanction as soon as the schedule and wording are determined."
