The BBC is planning a TV retrospective of the work of Sir David Attenborough next year in a move that may signal the twilight of the naturalist's career.

The series, which has the working title Life Stories from a series of Radio 4 lectures he has been giving since 2009, will look back on his life's work to mark 60 years since he joined the BBC in 1952. According to a senior BBC natural history source, the project, due to be formally approved soon, indicates that the 84-year-old may soon be calling it a day.

Attenborough is due to return to the BBC this autumn with a seven-part series called Frozen Planet, following the cycle of the polar seasons, which took three years to film and saw him film at the north pole for the first time. "He was much more involved in the making of this than he has been with other series and is on screen a lot more," said the BBC source, who added it was unlikely Attenborough would make another large-scale project for the corporation along the lines of Frozen Planet or his other epic series, such as Blue Planet or Planet Earth.

"Frozen Planet took three years to film and David braced seriously cold temperatures that most people, let alone someone in their eighties, could not endure. These projects don't happen very easily and I'd be very surprised if he makes another major BBC natural history series," said the senior source. "He is 85 this year and you cannot go on forever."

Towards the end of Frozen Planet Attenborough will deliver what the BBC source called a "big polemic" on his views of nature and the environment in what the insider identified as something akin to a final word on his life's work.

The episode, called Meltdown, will be a "look at what the future might hold for the animals and people that live at the poles and what these changes might mean for the rest of us", according to the BBC.

"The poles – north and south – look superficially very similar, but when you visit them within a few weeks of one another, as I have just done, you realise how profoundly different they are – and how what is happening to them is going to affect the entire planet," Attenborough said in pre-publicity for this autumn's series.

"A century ago the poles were just about the most inaccessible places on earth. Today that has changed. Nonetheless, to have visited them both within a few weeks of one another is a huge privilege."

Speculation about when he would stand down has long dogged Attenborough. In 2005 he told the Sunday Times that his work up until then had "given a series to every group of animals" and that he had made "enough".

Officially the BBC denies that Attenborough's career will be over after 2012 and Attenborough himself remains defiantly hopeful that he will go on. He is filming another 3D film for Sky about botanical work at Kew Gardens in south-west London. This follows his 3D film Flying Monsters for the broadcaster last year.

"Yes, I will be making Life Stories for 2012 to mark the anniversary, and I am not sure how much original filming it will involve," he said . Asked if he would continue with his filming work, he said: "I sincerely hope so, yes."

BBC's elder statesman

It is almost impossible to imagine the BBC without Sir David Attenborough, just as it is difficult to picture the presenter and naturalist making programmes for anyone other than the BBC.

Attenborough, who will be 85 in May, makes genuinely popular programmes with a strong educational element, the type of content that even the corporation's most vehement critics habitually applaud. Few, if any, broadcasters embody the BBC's mission statement to educate and inform more fully than he does. At times his name has been employed by executives as a two-word riposte to accusations it was dumbing down.

When Attenborough first applied to join the BBC in 1950 as radio producer, his application was rejected but he was offered a job in TV. Four years later he presented the first edition of Zoo Quest, which ran for a decade. His 1979 series, Life on Earth, was the most ambitious natural history series ever undertaken.

But Attenborough had a long spell as a BBC executive between the two landmark shows. Soon after the 1964 launch of BBC2 under Michael Peacock he became the channel's second controller (from 1965), introducing the coverage of snooker when the channel went colour in the early 70s. Other programmes commissioned by Attenborough included Civilisation and The Ascent of Man. He could probably have been director general if he had wanted to, but has confessed he had no desire to lead the organisation.

Instead, he went back to making programmes, all of them multiple award-winning, including Blue Planet in 2001 and Planet Earth five years later. As an elder statesman of the BBC he has occasionally criticised the corporation, telling the Radio Times earlier this year its "sails need to be trimmed". He is currently working on a 3D series for Sky, perhaps the BBC's most bitter rival.

James Robinson

• This article was amended on 8 April 2011. The original said that Attenborough was the first controller of BBC2 when it launched in 1965. This has been corrected.