The public service broadcaster was found to have committed a "significant breach" of industry standards by not revealing that the voice of a documentary about the Gaza conflict was the son of a Hamas official, according to regulatory body Ofcom.
An inquiry by the media regulator into the programme Gaza: How to Survive a Warzone has found that the programme was "substantially inaccurate".
The head of the BBC had earlier expressed regret, stating there had been "a significant failing in relation to truthfulness".
The regulator has instructed the BBC to transmit a evening declaration about its conclusions.
"As this represents a serious breach of our rules, we are instructing the broadcaster to broadcast a announcement of our findings against it on BBC2 at 21:00, with a timing to be determined," it said.
'Potential to Undermine Confidence'
The regulator's announcement stated: "Our probe found that the programme's lack of disclosure that the voice's father held a position in the Hamas-controlled government was substantially inaccurate.
"This implied that the audience did not have critical information which may have been extremely pertinent to their assessment of the narrator and the details he provided.
"Confidence is at the heart of the connection between a television network and its public, particularly for a state-funded media outlet such as the public broadcaster.
"This failing had the risk to erode the exceptionally strong degrees of trust that audiences would have put in a BBC factual programme about the Israel-Gaza war."
The documentary was withdrawn from the BBC's streaming service in the month of February after the presenter's familial connections were revealed, and in the month of July an corporation's own inquiry concluded it breached the organization's content policies on factual correctness.
A BBC spokesperson commented: "The authority's determination is in line with the conclusions of the corporation's inquiry, that there was a major oversight in the programme in relation to the broadcaster's journalistic policies on factual correctness, which corresponds to clause 2.2 of the regulator's media standards.
"We expressed regret for this and we comply with the authority's determination in its entirety. We will adhere to the sanction as soon as the date and wording are determined."
