Prince William is raising the stakes with BBC in row, and putting at risk future projects.
Kate and he already have banned the corporation showing their charity carol concert, which would be held at Westminster Abbey.
William, 39, was infuriated by a BBC Two documentary airing ‘unfounded’ claims that he and his staff briefed the media against Harry and Meghan.
Insiders now suggest that the ITV Christmas concert could just be the tip.

Prince William angered by ‘unfounded” claims made in BBC Two’s documentary. His staff also briefed media on Prince Harry’s and Meghan Markle.
Insiders at ITV confirmed that they had been offered the show late last week. They are currently negotiating with BBC Studios for a fee.
One source said it was clear that William, who worked with the BBC over his Earthshot Prize but is protective of his staff and their reputations, would have to ‘seriously consider’ any further projects.
That could extend to senior royals. They have been angered, not just by the claims made in the documentary, called The Princes and the Press, but also by the broadcaster’s approach to the project.
The BBC refused to allow William as well as Buckingham Palace and Clarence House – the households of the Queen and the Prince of Wales – to view the two-part programme in advance.

The Royal box is occupied by Queen Elizabeth II and Prince Charles.
The corporation did offer a ‘right of reply’ but it is understood the claims outlined in its memo to them were extremely ‘vague’.
‘It’s fair to say that while the response to what has happened is being driven by the duke, there is complete unity among all three royal households,’ a source with knowledge of the situation said.
‘You really couldn’t get a cigarette paper between them. There is a serious issue of integrity at stake here.’
According to sources, William remains deeply traumatized by the Martin Bashir scandal. This has yet to be discussed in Amol Rajan’s two-part documentary.
Last year, Mr. Bashir was found to have falsified documents to convince Princess Diana to talk to Panorama about her 1995 sensational interview.
Earlier this year William attacked both the journalist himself and the BBC’s management structure for deceiving his mother. He said their actions had fuelled her ‘fear, paranoia and isolation’ and hastened his parents’ divorce.
‘The whole Bashir scandal is still very raw for him – and now this,’ said a friend.
The Princes and The Press’s first episode covered media coverage about the young princes between 2012 and 2018, and how that was affected by their mother’s death.
It suggested there was ‘competitiveness’ between the different royal households and that, according to Omid Scobie, co-writer of the flattering Harry and Meghan biography, Finding Freedom, negative stories were deliberately leaked against Meghan to ‘put her in her place’.
According to reports, the BBC doesn’t plan on showing the royals any second episodes of the series before it airs Monday.

Jenny Afia, a lawyer speaking about The Princes and The Press document
According to insiders, the program will continue to focus on Harry’s relationship with William, and may contain more surprising revelations. The royal houses will probably wait to see Monday’s broadcast before taking any other action.
The complaint could be made to Ofcom. BBC chairman Richard Sharp yesterday said he hoped the Royal Family would ‘respect’ the documentary, said he stood by the programme’s producers and ‘hoped’ they got it right.
He added: ‘The BBC is a national institution and we approach our relationships with the other national institutions with great care and thought.
‘The Royal Family is at the centre of our identity. It’s underlying importance is unequivocal and we have tremendous respect for all aspects of the Royal Family in all that they undertake and do.
“From time to time this organisation produces programs that might or may not meet the full approval of different parts of Establishment. That is as true for government as it could be of the judiciary. It could also apply to other vital parts of society.
‘Our job is to get that right, is to be independent, to be respectful and fair.’