The company has put its local subsidiary CNR Ranger (Angola) up for grabs, and with it comes a 50% operating stake in barren block 16.

CNR International managing director Martin Cole said the asset failed to pass muster when it came to internal risk and investment thresholds.

"We are now nearing completion of our studies on this block and have concluded that although there is oil in nearby blocks, the risk associated with exploration is higher than expected," he said.

"CNR