The BBC committed a "serious breach" of broadcasting rules by omitting to mention that the voice of a documentary about the Gaza conflict was the son of a Hamas representative, according to British broadcasting authority Ofcom.
An investigation by Ofcom into the programme Gaza: How to Survive a Warzone has determined that the programme was "substantially inaccurate".
The BBC's director general had earlier expressed regret, noting there had been "a major oversight in relation to accuracy".
The regulator has instructed the broadcaster to air a evening announcement about its decisions.
"Given this constitutes a major infringement of our code, we are instructing the broadcaster to air a message of our determinations against it on BBC Two at 21:00, with a schedule to be determined," the statement read.
'Possibility to Undermine Credibility'
The watchdog's report stated: "Our investigation concluded that the programme's failure to disclose that the narrator's father held a role in the Hamas-controlled administration was substantially inaccurate.
"This implied that the audience did not have vital facts which may have been extremely pertinent to their evaluation of the voice and the content he presented.
"Credibility is at the core of the relationship between a media organization and its viewers, notably for a national broadcasting corporation such as the BBC.
"This oversight had the possibility to erode the significantly high levels of trust that viewers would have invested in a BBC factual programme about the Israel-Gaza war."
The film was withdrawn from the BBC's streaming service in February after the presenter's family links emerged, and in this past July an corporation's own inquiry concluded it infringed the corporation's content policies on accuracy.
A BBC spokesperson stated: "The Ofcom ruling is in line with the conclusions of the corporation's inquiry, that there was a serious error in the documentary in relation to the BBC's Editorial Guidelines on truthfulness, which reflects Rule 2.2 of Ofcom's Broadcasting Code.
"We have apologised for this and we agree with the regulator's ruling in complete. We will adhere to the directive as soon as the timing and language are confirmed."
