Angola's state-run news agency says President Jose Eduardo dos Santos, one of Africa's longest-serving rulers, will quit in 2018.

The Angola Press Agency reported on Friday that 73-year-old dos Santos, who became president in 1979, announced during a ruling party meeting that he would leave politics.

At the meeting, dos Santos also called for more robust measures to be taken against mismanagement. His administration has faced accusations of corruption and mismanagement of the country's oil and diamond riches.

Forbes magazine has ranked Isabel dos Santos, the president's oldest daughter, as one of the richest people in Africa.

After Angola's civil war ended in 2002, the country became one of sub-Saharan Africa's top oil producers. The country's economy has struggled in the past year because of the fall in energy prices.