The decline in oil prices may continue for a year or so but will prove temporary as population growth spurs higher consumption and supports prices in the longer term, a leading Saudi petrochemicals executive said on Sunday.

The comments by Mohammed al-Mady, chief executive of the state-controlled petrochemicals producer Sabic, reported by Reuters, come as oil-dependent states in the Gulf grapple with demands to curtail public spending and speed up reform programmes. The price of oil has fallen by a quarter since the summer. Brent crude closed at $86.05 on Friday.

At a meeting of Gulf Co-operation Council finance ministers in Kuwait over the weekend, Anas al-Saleh, Kuwait’s finance minister, said oil exporters must “undertake comprehensive economic reforms, including the reform of imbalances in public finances”. To achieve this they must strengthen efforts to diversify away from oil, he said.