Tony Hayward, the former BP chief executive who runs Iraqi Kurdistan-focused Genel Energy, said oil prices are set to soar as OPEC has taken just six-months to stop the US shale oil boom in its tracks.

Speaking at the FT Commodities Global Summit in Lausanne, Switzerland, Mr Hayward said the Organization of the Petroleum Exporting Countries had shown itself to be "the most successful cartel in history", predicting oil prices would soon return to near $80 a barrel.

Mr Hayward said of OPEC's decision to hold production steady in the face of fast-growing US shale output:

The supply base is shrinking, they (OPEC) are maintaining their market share. It seems like it's been a big success.

Mr Hayward, who said he will take a less active role in the day-to-day running of Genel by the end of this year, said the rapid fall in drilling rigs in the United States would soon see US oil output slow or fall.

While Mr Hayward acknowledged some OPEC members had been hurt by the price crash, he said longer-term OPEC's decision to maintain production had been justified:

Over a 1-2 year time period, in terms of defending your market share, it's been a success... ...I would expect them to continue on the course they set. It's having exactly the consequences they envisaged.

Mr Hayward added that oil exports from the north of Iraq have risen to 650,000 barrels per day, as the Kurdistan Regional Government has expanded its pipeline infrastructure to allow more oil to flow to the Turkish port of Ceyhan.

Following a deal between the KRG and Baghdad in December, both federal government-produced barrels from Kirkuk and Iraqi Kurdistan crude have been exported from the north of the country.

Mr Hayward said:

At the moment they're working with Baghdad and it is all peace and harmony. If the deal fails then the Kurds have the ability to go on their own.

Financial Times