A report on armed conflict in Africa has shown that the cost to the continent's development over a 15-year period was nearly $300bn (£146bn).
Money spent on wars means less spent on development
The research was undertaken by a number of non-governmental organisations, including Oxfam.
It says the cost of conflict was equal to the amount of money received in aid during the same period.
This is the first time analysts have calculated the overall effects of armed violence on development.
The report says that between 1990 and 2005, 23 African nations were involved in conflict, and on average this cost African economies $18bn a year.
It concludes that African governments have taken encouraging steps at a regional level to control arms transfers, but that what is needed is a global, legally-binding arms trade treaty.
The president of Liberia, which is just starting to recover from a long civil war, Ellen Johnson-Sirleaf, also wrote the preface to the report.
She told the BBC "the proliferation of weapons is a key driver in armed conflicts".
"We need to restrict the supply of guns to African conflict zones - and an arms trade treaty is a vital way to do this", she said.
The BBC's Johannesburg correspondent Peter Biles says that some costs of war, such as increased military spending and a struggling economy continue long after the fighting has stopped.
Liberia's Defence Minister, Brownie Samukai told the BBC's Network Africa programme that to his knowledge expenditure this year alone included sums of $11m and $35m "for training, equipment, facilities, buildings and construction - a combination of these types of expenditure."
The researchers say that although the number of armed conflicts is falling in Africa there is no room for complacency, with little hope of a swift settlement in either Sudan or Somalia.
And some experts argue that Africa actually needs to increase its arms spending.
Helmoed-Romer Heitman - the Africa correspondent for Jane's Defence - told the BBC "in a lot of countries the primary problem is that the national security forces are too small, too ill-equipped and too ill-trained to actually provide any sort of security".
He cites the example of Cameroon which has some 12,500 troops to cover around 400,000 sq kms with no transport or reconaissance aircraft.
"Without helicopters for tactical movement", says Mr Heitman, "it's physically impossible for them to deploy to counter banditry or insurgency".
He concludes that most African countries need to spend more on military equipment - but primarily on transport such as helicopters to allow them to mobilise to deploy against the "bad guys".