Oil prices will reach $70 a barrel by 2020, says Opec

Oil producers' group Opec has said it expects oil prices to recover to $70 a barrel by 2020.

Prices have fallen from more than $110 a barrel in the summer of 2014 to less than $37 a barrel now due to oversupply and slowing demand.

But Opec said oil prices would begin to rise next year and, longer term, would rise due to higher exploration costs.

It expects the market share of Opec producers to shrink by 2020 as rivals prove more resilient than expected.

The group currently accounts for about 30% of the world's oil production, down from 50% in the 1970s.

Part of the reason for this decline is the emergence of vast quantities of shale oil produced in the US. This has also been factor in pushing down the price of oil to 11-year lows.

In its World Oil Outlook report, Opec said it expected supply growth from US shale to slow dramatically next year, as producers struggled to cope with such low prices.

Opec's strategy this year has been to allow prices to fall by maintaining production in the hope that, eventually, US shale producers will be forced out of business.Another factor in low prices, Opec said, was weaker economic growth, particularly in developing economies.

It highlighted China, where the "economy seems to be maturing and growth is decelerating faster than previously expected".

Credit: BBC