Saudi Arabia will shut its Yanbu refinery for 35 days in November for maintenance and to tie in three units to boost gasoline output to 60,000 barrels per day, a spokesman at state oil firm Saudi Aramco said yesterday.

The spokesman said the facilities a continuous catalyst regeneration unit, an isomerisation unit and a diesel hydrotreating complex would add 20,000 bpd of gasoline production and reduce sulphur content in diesel.

Saudi Aramco said in a statement on its website that the 35-day total refinery shutdown would be completed in December.

"In the month of November, a major milestone will begin that will change the refinery into a more complex one," said the Aramco statement.

"Tie-ins for the three major projects the Continuous Catalyst Regeneration Unit, the Isomerisation Unit, and the Diesel Hydrotreating Complex ... are included in the shutdown plan, as is a carefully crafted programme to extend the T&I cycle from the current five years to seven years," it said.

The Aramco spokesman said the current capacity of the refinery was 235,000 bpd. It produces LPG, gasoline, jet fuel, diesel oil and fuel oil.