The BBC was found to have committed a "major breach" of broadcasting rules by omitting to mention that the voice of a film about the Gaza conflict was the offspring of a Hamas representative, according to British broadcasting authority Ofcom.
An inquiry by Ofcom into the programme Gaza: How to Survive a Warzone has found that the programme was "substantially inaccurate".
The head of the BBC had previously apologised, stating there had been "a serious error in relation to accuracy".
Ofcom has instructed the corporation to transmit a evening statement about its findings.
"Since this amounts to a significant violation of our rules, we are instructing the corporation to air a message of our determinations against it on BBC2 at nine o'clock in the evening, with a timing to be confirmed," it said.
'Possibility to Erode Credibility'
The regulator's announcement declared: "Our investigation determined that the documentary's failure to disclose that the voice's parent held a post in the Hamas-controlled government was significantly deceptive.
"This implied that the viewers did not have vital facts which may have been extremely pertinent to their judgment of the presenter and the details he shared.
"Confidence is at the center of the bond between a television network and its public, notably for a national broadcasting corporation such as the BBC.
"This failing had the risk to undermine the exceptionally strong amounts of credibility that audiences would have placed in a documentary produced by the BBC about the Israel-Gaza war."
The film was withdrawn from the BBC's streaming service in last February after the presenter's personal associations came to light, and in the month of July an internal BBC review concluded it breached the broadcaster's content policies on factual correctness.
A corporation official said: "The authority's determination is in accordance with the results of the corporation's inquiry, that there was a major oversight in the documentary in relation to the BBC's Editorial Guidelines on factual correctness, which aligns with clause 2.2 of Ofcom's Broadcasting Code.
"We issued an apology for this and we comply with the regulator's ruling in its entirety. We will comply with the penalty as soon as the date and wording are determined."
