The BBC engaged in a "serious breach" of broadcasting rules by omitting to mention that the presenter of a documentary about Gaza was the son of a Hamas official, as determined by regulatory body Ofcom.
An investigation by Ofcom into the programme Gaza: How to Survive a Warzone has found that the documentary was "materially misleading".
The BBC's director general had already issued an apology, stating there had been "a serious error in relation to truthfulness".
Ofcom has directed the corporation to transmit a evening declaration about its conclusions.
"Given this constitutes a serious breach of our code, we are ordering the BBC to transmit a statement of our findings against it on BBC Two at 9pm, with a timing to be confirmed," the statement read.
'Possibility to Undermine Trust'
The watchdog's statement said: "Our investigation determined that the documentary's omission to reveal that the presenter's male guardian occupied a position in the Hamas-administered government was significantly deceptive.
"It meant that the public did not have vital facts which may have been very significant to their evaluation of the presenter and the content he shared.
"Credibility is at the heart of the connection between a broadcaster and its public, particularly for a state-funded media outlet such as the British Broadcasting Corporation.
"This failing had the possibility to damage the significantly high degrees of trust that viewers would have put in a BBC factual programme about the conflict in Gaza."
The film was removed from the online platform in the month of February after the presenter's familial connections emerged, and in July an broadcaster's internal assessment found it violated the broadcaster's content policies on factual correctness.
A representative for the broadcaster said: "The authority's determination is in agreement with the conclusions of the corporation's inquiry, that there was a significant failing in the documentary in relation to the broadcaster's journalistic policies on accuracy, which corresponds to regulation 2.2 of the authority's broadcasting regulations.
"We issued an apology for this and we comply with the authority's determination in complete. We will adhere to the sanction as soon as the date and language are determined."
