A maverick nationalist is threatening to unseat Zambia's donor- and investor-friendly government in next week's general election. Opinion polls show Michael Sata's Patriotic Front gaining on - and possibly even defeating - the Movement for Multiparty Democracy of incumbent President Levy Mwanawasa, which has governed Zambia since 1991.

The 69-year-old Mr Sata, nicknamed "King Cobra" for his blunt style, has been making populist economic pledges to Zambia's poor on a vigorous whistlestop campaign through the bush. In doing so, he has rattled western aid donors and Chinese investors, both objects of his criticism.