- Most of the units at the 404,000 barrels per day Pernis oil refinery in Rotterdam operated by Royal Dutch Shell were shut following a power supply fire.

- "Shell Pernis is a catalyst behind the stronger market," said a Singapore-based trader.

NAPHTHA TENDERS: Taiwan's CPC bought full-range naphtha for September arrival at a premium of about $1 a tonne to Japan quotes on a cost-and-freight (C&F) basis.

- Spot prices in South Korea, Asia's top naphtha importer by volumes, were in discounts last month for cargoes scheduled for first half August to first-half September delivery.

STOCK LEVELS: Analysts forecast that stockpiles of US gasoline USOILG-ECI declined 1.1 million barrels in the week ended July 28, a preliminary Reuters poll showed on Monday.

OTHER NEWS: Indian refiners are outperforming their competitors in South Korea and Thailand as they have ramped up output from new fuel and chemical capacities to meet rising domestic demand.