Zambian political parties on Monday wrapped up their campaigns ahead of a special presidential election called following the death of president Michael Sata last year.

The ruling Patriotic Front (PF) held its final rally in Lusaka's Woodlands suburb, presenting a united front at a rally after a bitter succession battle left it scarred. 

Zambians head to the polls on Tuesday in a special election to chose a new president for the copper-rich southern African nation and replace Michael Sata who died last year.

The contest is expected to be close between two frontrunners -- Defense and Justice Minister Edgar Lungu, 58, and opposition leader Hakainde Hichilema, 52.

Zambia's acting president Guy Scott on Wednesday rejected a call for his resignation by a majority of cabinet ministers, and suggested a meeting they held without him had been treasonous.

Scott said he was the only one mandated to call a cabinet meeting and "any other meeting purporting to be a cabinet meeting constitutes a serious act of treason".

A major split in Zambia's ruling Patriotic Front (PF) has seen two factions select rival candidates for presidential elections next month, raising the possibility that the opposition could snatch victory.

A faction loyal to acting president Guy Scott chose late president Michael Sata's nephew Miles Sampa as its candidate on Monday night, a day after Defense Minister Edgar Lungu was named by a breakaway group.

Zambia's governing Patriotic Front party on Friday suspended Guy Scott from the party, weeks after he took over as interim president of the country following the death of Michael Sata last month.

Scott will however remain acting president of the country.

Zambia's opposition was plunged into crisis just weeks before elections Monday as former president Rupiah Banda claimed he had wrested the party's nomination from a rival and vowed a political comeback.

Elections in the copper-rich nation are due within months, following the death in office of 77-year-old president Michael Sata, who passed away in London in October from an undisclosed ailment.

The battle to succeed late Zambian president Michael Sata has entered the courts, with supporters of one contender claiming that his right to take over as interim president had been unlawfully denied.

Court documents seen on Thursday show former education minister Newton Nguni is seeking a reversal of the decision by the cabinet and Attorney General to hand power to Vice President Guy Scott.

Zambian Vice President Guy Scott was named acting head of state Wednesday following the death of President Michael Sata, making him Africa's first white leader since South Africa's FW de Klerk.

Defense and Justice Minister Edgar Lungu said Scott would occupy the office until an election is held, likely to be within 90 days.

Zambia's government on Wednesday announced 77-year-old President Michael Sata had died in London of an unspecified illness, leaving behind questions about who will now lead the copper-rich African nation.

"It is with a heavy heart that I announce the passing on of our beloved president," government cabinet secretary Roland Msiska said in an address to the nation.

At least 20 people, mainly schoolchildren, are believed to have died in Zambia after a boat capsized during celebrations for the nation's golden anniversary of independence, the state-run news service reported Friday.

The boat went down on Lake Kariba in the southern African nation, with three teachers and 21 pupils on board, the ZANIS agency reported, citing a police source.