Asia's naphtha crack fell to one week low of $17.50 a tonne on Tuesday as supplies build up due to high volumes of east-bound cargoes, industry sources said.

South Korea's YNCC paid a discount of about $6 a tonne to Japan quotes on a cost-and-freight (C&F) basis for an open-specification naphtha cargo scheduled for second-half June arrival at Yeosu.

This was four times lower than the discount of $1.50 a tonne YNCC had paid on April 23 for naphtha scheduled for first-half June delivery.

Based on data from Refinitiv Oil Research, the total naphtha flows into Asia for May have been notionally assessed at up to 6.5 million tonnes.

This was significantly higher from April's volumes of up to 4.8 million tonnes, mainly due to Western supplies arriving in the East hitting a historical high, the data showed.

Cargoes arriving from the West including Europe to Asia this month are seen at nearly 2.9 million tonnes, the weekly report said.

Asia's gasoline crack was at a discount of 90 cents, versus a discount of 24 cents in the previous day.

But industry sources expect demand to improve due to the gradual easing of lockdowns across the world.

Indian refiners are scaling up crude processing as local fuel demand begins to improve.

Northwest European gasoline refining margins on Monday rose above $5 a barrel following a long weekend, buoyed by some tentative signs of a recovery in demand.