Top oil exporter Saudi Arabia may increase official selling prices (OSPs) of October crude for Asian clients, as refiners across the continent process more, aiming to benefit from attractive margins for products from fuel oil to jet fuel.

All seven traders participating in a Reuters poll on Wednesday project the price of Arab Light will rise, with gains expected in a range between 15 and 80 cents to a premium of 90 cents-$1.55 a barrel to the average of Oman and Dubai quotes.

Expectations that idled refineries will resume production in China and Taiwan, poor economics to ship Atlantic Basin crude to Asia and tighter prompt supplies over the past month triggered a sharp uptrend in valuations for Middle East crude.

Spot cargo premiums have rebound to levels not seen since Saudi Arabia unilaterally boosted oil output towards 10 million barrels per day (bpd) in June. The benchmark Dubai swaps curve shifted from a structure denoting ample supplies, known as contango, to the backwardation reflective of a tighter balance.

'The Dubai benchmark price is quite attractive and everybody has been rushing to buy,' said a trader with a northeast Asian refiner of Saudi crude.

'Refineries are coming back from maintenance, while the tightness in Europe means there are limited imports and cargoes priced off Dubai are even moving into the Mediterranean.'

Prospects that Libya will resume oil exports under a new government after a six-month interruption triggered by civil war have done little to narrow the premium of European benchmark Brent crude to Dubai. <DUB-EFS-1M>

A resumption of output in the North African country would weigh on values of Saudi Arab Extra Light and Super Light crudes, for which prices are expected to increase much less than for Arab Heavy and Arab Medium.

Concerns about a global economic slowdown as economic indicators deteriorate in Europe and top oil consumer the United States may temper the increase in Saudi OSPs, some traders said.

'The Saudis don't want to rock the boat too much when it is almost teetering into recession,' a trader with a European trading firm said. 'They know Libya will come back and increase competition in lighter grades.'

State oil company Saudi Aramco last month already lowered the price of Arab Light by a larger-than-expected 60 cents, weighed down by refinery snags in China, Taiwan and India.

But PetroChina is restarting a crude unit at its largest refinery in Dalian and will begin normal operations by the end of this month , while Taiwan's Formosa Petrochemical Corp's last week restarted a crude distillation unit at its 540,000-bpd Mailiao plant.

Saudi crude OSPs are usually released around the fifth of each month, and set the trend for Iranian, Kuwaiti and Iraqi prices, affecting around 8 million barrels per day (bpd) of crude bound for Asia.

State oil giant Saudi Aramco sets its crude prices based on recommendations from customers and after calculating the change in the value of its oil over the past month, based on yields and product prices.-Reuters