Traders with oil majors said that any stocks currently held are reserved for contract customers.

"The tanks are almost dried up and replenishment stocks aren't expected until early next month," one supplier said.

Only one major was quoting, selectively, offering small quantities of less than 500 tonnes of 180-cst at $100-$102 per tonne on Thursday.

Hong Kong's predicament arose from the delay in the arrival of replenishment stocks, which was in turn caused by an acute shortage in Singapore.

"We supply our affiliate in Hong Kong from Singapore, and if we are short, they too will suffer," a trader with a US oil major in Singapore said. An increase in demand from Hong Kong also exacerbated the problem, traders said. China, for one, had been buying quite frequently even though the volume was rather small,between 2,000 and 5,000 tonnes per lifting, they said.

Recent demand for bunkers in Hong Kong had been healthy because prices there were at least $8-$10 lower than those offered in Japan, traders said.

Most traders said they expected the supply tightness to ease only by mid October when replenishment stocks would have been in place.

Japan has also been hit hard in recent weeks by a shortage of fuel oil due to refinery throughput cut backs and scheduled maintenance shutdowns, traders said.

In Japan, prices for 180-cst were much higher at $105-$106 and 380-cst at $102-$103.

"Our stocks are very, very limited right now and if shipowners want to buy, they must be prepared to pay," one supplier in Tokyo said.

But traders said shipowners could either divert to other relatively cheaper ports in Singapore or South Korea to take bunker.

Singapore and South Korea are currently the two cheapest ports offering bunkers in the region, traders said.

In South Korea, prices for 180-cst bunkers were at $87-$88and 380-cst at $84-$85.

Singapore's bunker prices were offered at almost on par with South Korea to slightly lower, traders said.

"We are getting quite a fair bit of inquiries from shipowners today, more than the previous days," one supplier in Singapore said.