Africa's largest free-trade zone is to be created, covering 26 countries and including more than 600 million people.

The deal, due to be signed in Egypt, is intended to ease the movement of goods across member countries which represent more than half the continent's GDP.

Since the end of colonial rule, governments have been discussing ways to boost intra-African trade.

The poor state of roads, railways and national airlines have made it difficult to move goods across borders.

Three existing trade blocks - the Southern African Development Community (SADC); the East African Community (EAC) and the Common Market for Eastern and Southern Africa (Comesa) - are to sign the treaty to create the new zone.

The pact - known as the The Tripartite Free Trade Area (TFTA) - will then be officially unveiled at the upcoming summit of the African Union this weekend in South Africa.

The BBC's Africa business reporter Lerato Mbele says the idea behind it is to remove trade barriers on most goods, which will stimulate $1tn (£648bn) worth of economic activity across the region.

However, concluding the deal in Egypt will merely be the first step and it will need to be approved by each countries' parliament, before the wheels are set in motion, she says.

It is hoped that this will happen by 2017. 

Agencies