"The currencies of African oil countries diverge. Africa's two largest oil producers have suffered similar losses in their currencies this year as fuel price fluctuations have reduced foreign exchange inflows. Angola's Kwanza is down about 30% since the beginning of the year against the dollar, reflecting the decline of the Naira in the parallel market.

Yet the outlook for the two currencies looks divergent as the pressure on Angola from rising debt-related service charges increases," the publication reads. According to Fitch, adds the same source, the level of Angolan public debt is heading towards 129% of GDP or 850% of state revenues.

The rating agency downgraded Angola from B- to CCC on Friday. While Angola may turn to multilateral lenders and its sovereign wealth fund to meet its obligations this year, we expect sustained pressure on the Kwanza as declining reserves weaken confidence.

According to Aza Finance, the rise in Naira triggered by the resumption of dollar sales by exchange offices and speculators reducing dollar positions ended this week, as bdc sales in dollars were insufficient to meet demand.

"The market has fallen to $445 per dollar in the parallel market from $440 last week. The Bdcs still have a huge backlog on their foreign exchange obligations, which will continue to put pressure on the naira in the coming days, as well as the economic context of declining revenues and oil reserves," it said.

Aza Finance reveals that the Rand lost nearly 2% against the dollar, from 16.62 to 16.97, after South Africa's GDP in the second quarter collapsed by 51%.

As for Kenya's shilling, Aza Finance points out that it fell slightly against the dollar to 108.55 due to strong dollar demand from the energy sector.