LARKANA (Pakistan) - THE party of Benazir Bhutto is to publicly release her will on Tuesday to prove that it names the slain Pakistani opposition leader's husband as her political heir, officials said.

The move follows a whispering campaign that the document had not named her spouse Asif Ali Zardari, and that she had instead picked their 19-year-old son Bilawal to lead the Pakistan People's Party (PPP).

A copy of the handwritten will dated Oct 16 - two days before she returned to Pakistan from exile and just over two months before her assassination - was posted on the website of the US magazine Newsweek.

'He spent 11 1/2 years in prison without bending despite torture. He has the political stature to keep our party united.'

Mr Zardari spent the time in jail on allegations of corruption and of involvement in the killing of Bhutto's brother, Murtaza, in 1996. He was never convicted and was freed in 2004.

'This is the will and it is going to be released by the party today in Naudero,' the ancestral home of the Bhutto family, PPP spokesman Farhatullah Babar told AFP.

The party named Mr Zardari and his son as co-chairmen on Dec 30 after the will was read out to senior party members, but not to the public.

'This was read out as part of her will by chairman Bilawal Bhutto Zardari in the meeting' on December 30, senior party official Taj Haider told AFP.

'It was on the basis of this letter that Mr Zardari was given the leadership and on his proposal Bilawal was made the chairman. The party unanimously accepted these decisions,' he said.

Addressed to the 'officials and members' of the party, the letter says Bhutto was 'honoured' to lead them and urges them to continue her work.

'I fear for the future of Pakistan. Please continue the fight against extremism, dictatorship, poverty and ignorance'.

Mr Zardari and the party are set to kickstart campaigning for Feb 18 general elections when the official mourning period for Bhutto ends later this week.

Bilawal is currently studying in Britain. -- AFP