A leading figure inside the ruling Zanu-PF party in Zimbabwe is planning to mount a challenge to the leadership of Robert Mugabe, the BBC can confirm.
Simba Makoni was once finance minister under Mr Mugabe but now looks set to run against him in national elections expected in March.
The BBC's John Simpson confirmed the news while under cover in Zimbabwe.
Mr Makoni is seen as a moderate within Zanu-PF but the party has already said Mr Mugabe will be its candidate.
Our correspondent reports that there is growing opposition to Mr Mugabe from within the ranks of his own party.
Although there is serious discontent at Mr Mugabe's dictatorial style of leadership within the general population, our correspondent says, a popular uprising seems unlikely due to the harsh repression of opposition in Zimbabwe.
BBC News is banned in Zimbabwe - though widely watched on satellite TV - so our correspondent spent his week-long visit to the country under cover.
He reports that much of life in Zimbabwe now consists of waiting - at the bank for banknotes amid galloping inflation, at the petrol stations for fuel, and in lines for food.
He says people are also waiting to see what happens politically in 2008.
Mr Makoni is seen as a reformer and a moderate
The economic crisis has, in some senses, served Mr Mugabe well, our correspondent says - making Zimbabweans ever more dependent on the state and strengthening government control of the populace.
Mr Makoni has been mentioned as a possible compromise candidate between different Zanu-PF factions and even the opposition for many years.
However, while he is well respected among the political classes, correspondents say he does not have a strong grass-roots support base.
After being sacked as finance minister in 2002, he moved to South Africa.
Political commentator John Makumbe last week said reports that Mr Makoni was launching his own presidential campaign were "the joke of the year that we didn't expect so soon".