The group has also negotiated exclusive rights to handle all the marketing and transport of oil and commodities, tying up several deals negotiated over the past five years.

All the accords were reached before the Comprehensive Peace Agreement (CPA), which ended the 22-year civil war in January 2005.

The Juba-based government of South Sudan has insisted that such deals must be respected regardless of whether the North opts to ratify them, although new contracts must pass through the National Petroleum Commission, which also includes officials from the North.

Jarch