The public service broadcaster engaged in a "serious breach" of media regulations by not revealing that the presenter of a film about Gaza was the offspring of a Hamas representative, according to regulatory body Ofcom.
An probe by the media regulator into Gaza: How to Survive a Warzone has concluded that the programme was "materially misleading".
The BBC's director general had previously apologised, saying there had been "a serious error in relation to accuracy".
The regulator has instructed the broadcaster to transmit a evening declaration about its findings.
"As this represents a major infringement of our rules, we are instructing the corporation to broadcast a announcement of our findings against it on the BBC's second channel at 9pm, with a schedule to be confirmed," the regulator stated.
'Potential to Damage Confidence'
The regulator's report stated: "Our probe concluded that the documentary's omission to reveal that the presenter's male guardian occupied a post in the Hamas-controlled authority was materially misleading.
"This implied that the public did not have essential details which may have been extremely pertinent to their assessment of the presenter and the information he provided.
"Credibility is at the heart of the relationship between a media organization and its public, notably for a national broadcasting corporation such as the public broadcaster.
"This error had the risk to undermine the very considerable levels of credibility that viewers would have put in a factual film from the broadcaster about the Israel-Gaza war."
The programme was removed from iPlayer in last February after the presenter's personal associations emerged, and in the month of July an internal BBC review found it violated the broadcaster's editorial guidelines on truthfulness.
A representative for the broadcaster stated: "The authority's determination is in accordance with the results of the corporation's inquiry, that there was a significant failing in the programme in relation to the BBC's Editorial Guidelines on factual correctness, which reflects clause 2.2 of the regulator's media standards.
"We have apologised for this and we accept the regulator's ruling in complete. We will comply with the sanction as soon as the schedule and language are confirmed."
