Nigeria's state-owned oil company says an oil tanker carrying 800,000 litres of stolen crude has been intercepted offshore while heading to Cameroon.

It said the vessel would be destroyed as a deterrent.

Nigeria's state-owned oil firm said the oil had been stolen from a well in the south-western state of Ondo.

Oil theft from pipelines and wells in the Niger Delta is a major problem for the Nigerian economy, robbing it of much-needed revenue.

The oil company said that the Nigerian registered tanker had been operating in what it called stealth mode for the last 12 years.