The decision to withdraw from the Armed Forces of Angola (FAA) marked a serious escalation of the growing controversy over the 29-30 September legislative and presidential elections. It followed a threat by Mr Savimbi on Saturday to resume fighting.
Unita has accused the government of intimidation and theft of ballot boxes to steal the election.
The FAA was set up earlier this month to merge the two armies, one loyal to Unita and the other to the government, in a United Nations-backed programme involving British, French and Portuguese military instructors.
Most independent international observers have described the election as free and fair, although repeated delays in the count has heightened tension in Luanda. Latest returns show President Jose Eduard dos Santos, leader of the Popular Movement for the Liberation of Angola (MPLA), leading Mr Savimbi in the presidential election by 51.3 per cent to 38 per cent.
The action by Mr Savimbi's National Union for the Total Independence of Angola (Unita) came after a statement by senior Unita officials that they 'categorically rejected the process' of the elections. Abel Chivukuvuku, a Unita spokesman, called the vote a 'generalised systematic fraud'.
In a meeting between officials of the National Electoral Council and members of Angola's 19 political parties, Mr Chivukuvuku demanded that Unita be allowed to verify the voters' sheets.Reuse content