The ex-wife of former Zambian president Frederick Chiluba is claiming more than $2.5 billion - equivalent to more than three-quarters of the country's Gross Domestic Product - as part of a divorce settlement.

Vera Chiluba, whose marriage of 33 years was annulled last year, is also claiming a share of the couple's concrete assets, which she says include six houses and a farm.

In addition, she is demanding that Mr Chiluba hand over 400 cows, sheep and goats.

Vera Chiluba says her former husband can afford such a settlement and that she can prove it.

The case is due to come to court in early June.

Reduced pension

The BBC's Richard Lee in Lusaka says few Zambians will believe that their former president accumulated such vast wealth during his decade in office.

But our correspondent says the claim is likely once again to focus attention on whether Mr Chiluba should be stripped of his immunity as an ex-President, in order to answer allegations of corruption.

Mr Chiluba left office last December, after failing to muster enough support to contest an unconstitutional third term as head of state.

Earlier this month, a judge ordered him to stop using government-owned facilities and personnel.

He had to give up his Mercedes, a number of other vehicles, the keys to a government-owned house, as well as security guards and domestic staff.