A spokesman for ITN claimed that the decision by police followed a report on ITV News at Ten last night critical of the police investigation, and accused the police of an "attempt to censor what information we can broadcast."
Avon and Somerset confirmed this afternoon that they have lodged a complaint with Ofcom over the report.
"We have made a complaint to Ofcom in respect of the unfair, naïve and irresponsible reporting on the ITN ten o'clock news yesterday evening.
"As we are still awaiting a response to our complaint it would be inappropriate for us to comment any further at this time.
"A live murder investigation has been underway now for just twelve days and the media have played an important role in helping us to appeal for witnesses. While we appreciate the support we have received so far from most of the media we must step in if we feel coverage will hamper the investigation. Our primary aim will always be to secure justice for Joanna."
The spokesman for ITN said the broadcaster was "hugely disappointed" by the decision to exclude ITV News from today's press conference.
"This decision will result in millions of viewers not being able to see new evidence or hear the latest police calls for witnesses."
ITN claim that Avon and Somerset police was contacted "numerous times" prior to broadcast but "did not use this opportunity to register any issues or raise a complaint with ITN".
Index: Due process, prejudice and the press in the case of Chris Jefferies