The 63-year-old musician is teaming up with his 'Billy Elliot' co-writer Lee Hall to pen a new stage production based on George Orwell's book 'Animal Farm'.
However Lee – who won Olivier and Tony awards for his book and lyrics for the musical 'Billy Elliot' and an Oscar for the movie – admitted that the musical will not be completed any time soon.
He said: "I would think it's going to take about two years before it's all ready to go".
The writer also revealed that the 'Rocket Man' hitmaker prefers the lyrics to be written before he begins to work on the music.
He explained to the Daily Mail newspaper: "Having worked with him on 'Billy Elliot', I know that Elton likes to have the lyrics done and have them in front of him so I'll work on a batch before I give him anything to look at."
And the writer said he is "deep into it, writing songs for pigs and other four-legged friends."
'Animal Farm', an allegorical novel based on events in the Soviet Union tells the story of a piglet called Napoleon who destroys his opponents in a bid to control the old Manor Farm.
There is no producer attached to the project yet, with Lee saying that he and Elton would get others involved when the show is near completion.