SINGAPORE, March 26 (Reuters) - Light sweet crude weakened in Asia on Monday as Petronas sold its second cargo of Tapis crude at a lower premium after naphtha cracks slipped to their lowest in about a month. Naphtha's fall could weigh on other light sweet grades such as Cossack, Kitan and North West Shelf (NWS) condensate, which are still available for May loading. * TENDERS - Malaysia's Petronas sold the 300,000-barrel Tapis cargo for May 24-30 loading to an oil major at a premium of $6.70 a barrel to dated Brent, traders said. - BP's joint venture in Russia, TNK-BP, sold three cargoes of ESPO Blend crude at higher premiums than the previous month, as its value rebounded on firm demand in Asia, traders said. The producer sold two cargoes to Gunvor and one to Shell at premiums between $4.15 and $4.30 a barrel to Dubai quotes, they said. The sales took place late on Friday, and the cargoes will load on May 3-10, 14-17 and 26-29. - Formosa Petrochemical bought a cargo of Russian ESPO crude via a tender for April, trade sources said. The Taiwanese refiner bought the cargo from Vitol at a low premium of $3.88 a barrel to Dubai quotes, they said. - Vietnam's PV Oil has issued a tender offering only one cargo of Chim Sao for loading on May 25-29 as bad weather delayed earlier liftings, trade sources said. The tender will close on March 29 with bids valid until April 3. - Taiwanese refiner CPC bought 2 million barrels of Cabinda from Chevron, 1 million barrels of the same grade from Unipec and 1 million barrels of Zafiro, likely from ExxonMobil, for May delivery in a tender, traders said. * MARKET NEWS - Shell unexpectedly shut on Monday a gasoline-making fluid catalytic cracker (FCC) at the 500,000 barrel-per-day (bpd) refinery and is currently restarting the unit, trading sources said. However, it was unclear if other units at the complex had been affected and how long the outage would last. - South Sudan hopes to resolve a row over oil and other outstanding issues with Sudan within a month or two, South Sudan's top negotiator said on Saturday, pointing to an easing of tensions between the two old civil war foes. - Southwestern Japanese utility Kyushu Electric Power Co 9508.T said on Monday it shut the 500-megawatt oil-fired No.2 unit at its Sendai power plant earlier in the day due to a unspecified problem. CRUDE Price Prev Change MAY Oman diff to Dubai 2.15 2.33 -0.18 MAY Brent 124.95 123.68 1.27 MAY Dubai 120.81 119.93 0.88 MAY DME Oman 122.96 122.26 0.70 MAY Brent/Dubai EFS DUB-EFS-1M 4.14 3.75 0.39 PRODUCT CRACKS Price Prev Change APRIL gasoil crack -7.09 -6.47 -0.62 APRIL fuel oil crack 14.91 14.96 -0.05 MAY naphtha crack -7.27 -7.15 -0.12 COMPLEX REFINERY MARGINS Today 5.29 Last 5 days 5.27 Last 365 days 7.75

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