Traders said the four cargoes, loaded over the past two weeks for arrival in May, were likely to be a blend of straight-run 280-centistoke (cst) fuel oil and Sudan's Dar Blend crude.

'The mix is a blend of Iranian 280-cst and Dar Blend. Its cheaper and the mix is close to the Russian fuel oil grade,' a Singapore-based trader familiar with at least one shipment said.

This is the first time in nearly a year that independent Chinese refiners have bought fuel oil from Singapore, shipbrokers and traders said.

Traders said that if such shipments became more regular, this could offer a lift to the spot market, providing traders with another export option besides Southern China.

But for now, Singapore fuel oil prices versus Dubai crude oil remained at a discount of US$20 (S$27) to US$22, close to a record-low discount of US$23 due a glut in Singapore storage tanks with the higher arrivals of Western arbitrage barrels.

'It's too early to say, but with cracks at near record lows, any additional demand will help improve that,' a Singapore-based trader said.

Asian traders said tighter supplies of Russian straight-run fuel oil (M-100) due to strong demand from a top Japanese refiner seeking cheaper refinery feedstocks, had forced China's private refiners in the north to seek alternatives. -- REUTERS