The BBC was found to have committed a "significant breach" of industry standards by not revealing that the presenter of a documentary about the Gaza situation was the offspring of a Hamas official, as ruled by UK media regulator Ofcom.
An probe by the broadcasting watchdog into the programme Gaza: How to Survive a Warzone has found that the film was "materially misleading".
The BBC's director general had already issued an apology, stating there had been "a significant failing in relation to truthfulness".
Ofcom has ordered the broadcaster to air a peak-time declaration about its decisions.
"Given this constitutes a significant violation of our regulations, we are instructing the broadcaster to broadcast a message of our findings against it on BBC2 at nine o'clock in the evening, with a date to be confirmed," the statement read.
'Possibility to Undermine Credibility'
The authority's statement stated: "Our investigation found that the programme's lack of disclosure that the narrator's male guardian served in a role in the Hamas-run authority was substantially inaccurate.
"It meant that the audience did not have critical information which may have been very significant to their evaluation of the presenter and the content he shared.
"Confidence is at the core of the connection between a television network and its audience, particularly for a state-funded media outlet such as the British Broadcasting Corporation.
"This oversight had the possibility to undermine the significantly high degrees of trust that the public would have put in a documentary produced by the BBC about the Gaza conflict."
The documentary was removed from the online platform in February after the presenter's personal associations came to light, and in this past July an broadcaster's internal assessment concluded it violated the broadcaster's content policies on accuracy.
A corporation official stated: "The authority's determination is in agreement with the results of the corporation's inquiry, that there was a major oversight in the programme in relation to the BBC's Editorial Guidelines on truthfulness, which reflects clause 2.2 of the authority's broadcasting regulations.
"We have apologised for this and we agree with the regulator's ruling in its entirety. We will comply with the sanction as soon as the timing and wording are confirmed."
