Media consultant Alice Enders has claimed the BBC's world renowned wildlife shows could be next in line for cuts due to their high production budgets.
The original Planet Earth in 2006 cost £16million to make.
'If the licence fee continues to wither, you are looking at the BBC's big-ticket items to make savings so nothing can be immune,' Ms Enders told the i. 'David Attenborough's natural history series sell well globally but they are expensive too. There would need to be more co-productions with international broadcasters.'
Ms Enders warned big ticket drama could also be the focus of cost-cutting, adding: 'There could be less high-end drama, it's a big expense and streamers are forcing prices up.
'The costume budget alone for The Crown is huge.'