The BBC has "savaged" its staff by axing nearly 3,000 jobs, unions representing employees have declared.
Union leaders said the biggest job cuts in BBC history threatened to destroy the heart of the corporation.
But Director-General Mark Thompson insisted the losses are "the right price to pay" if the BBC is to remain "the greatest force for cultural good on the face of the earth".
The BBC is hoping to save £320 million per year, which will be put back into programme-making.
An initial 2,900 job losses have been announced, with further cuts expected in the New Year. The vast majority - some 2,500 posts - will go from administrative departments including human resources, finance, marketing, training and legal services.
A further 400 jobs will go in the corporation's factual and learning department. More redundancies are expected in March in news, radio, music, new media, regional and TV departments.
Mr Thompson made his announcement via a special internet broadcast yesterday.
In addition to the losses, 1,800 jobs - including BBC Sport, Radio 5 Live and all children's programming - are to be moved from London to Manchester. A number of the BBC's commercial ventures are also to be sold off, with the prospect of further job cuts.
Union leaders vowed to fight all compulsory redundancies and warned of possible industrial action.
In a joint statement, the National Union of Journalists, Amicus and Bectu said: "We are committed to working together to oppose at all levels the effects of the director-general's savaging of staff in the biggest cuts in BBC history. His announcements showed high-handed disregard for the future of thousands of staff, and threatened the very heart of the BBC.
"Far from preparing the BBC for charter renewal, we believe a policy which requires such colossal job cuts, reductions in programme commitments and the sale and privatisation of core sections of the BBC risks destroying its ability to continue as the UK's leading public service broadcaster, and poses a substantial risk to the BBC's continuing right to the licence fee."