The British broadcaster engaged in a "serious breach" of media regulations by failing to disclose that the presenter of a film about Gaza was the offspring of a Hamas representative, as determined by British broadcasting authority Ofcom.
An probe by Ofcom into Gaza: How to Survive a Warzone has found that the documentary was "substantially inaccurate".
The BBC's director general had previously apologised, saying there had been "a serious error in relation to truthfulness".
The authority has directed the corporation to air a evening announcement about its decisions.
"As this represents a significant violation of our rules, we are ordering the broadcaster to broadcast a message of our determinations against it on the BBC's second channel at 21:00, with a date to be determined," it said.
'Possibility to Damage Confidence'
The watchdog's announcement said: "Our probe found that the film's lack of disclosure that the narrator's parent occupied a position in the Hamas-controlled administration was substantially inaccurate.
"This implied that the viewers did not have essential details which may have been extremely pertinent to their evaluation of the presenter and the details he shared.
"Credibility is at the heart of the relationship between a media organization and its viewers, especially for a state-funded media outlet such as the British Broadcasting Corporation.
"This oversight had the risk to undermine the very considerable levels of credibility that the public would have placed in a documentary produced by the BBC about the Gaza conflict."
The documentary was pulled from iPlayer in February after the presenter's familial connections came to light, and in July an corporation's own inquiry concluded it breached the broadcaster's editorial guidelines on factual correctness.
A BBC spokesperson said: "The authority's determination is in line with the results of the corporation's inquiry, that there was a major oversight in the film in relation to the BBC's Editorial Guidelines on truthfulness, which corresponds to regulation 2.2 of the regulator's media standards.
"We issued an apology for this and we comply with the authority's determination in its entirety. We will comply with the directive as soon as the timing and language are determined."
