Sporadic power and water supplies returned to parts of Myanmar's biggest city of Yangon on Thursday and the prices of basic food dropped, signals of a gradual recovery from the onslaught of Cyclone Nargis.

Fuel prices, which reached 10,000 kyat (4.36 pounds) per gallon, also fell to 8,000 kyat after the junta relaxed its ban on private companies importing fuel to try to alleviate a chronic energy shortage.

The staple rice remains costly, but prices have stabilised with roads into the city from the north remaining open despite destruction of homes and other buildings in and around the former capital during the weekend cyclone. One egg now costs just 200 kyat. In the immediate aftermath of Nargis, it was 350 kyat - nearly three times the normal price.

About 23,000 people were killed, including nearly 700 in Yangon, the government said. More than 42,000 were missing in the worst cyclone to hit Asia since 1991, when 143,000 people were killed in neighbouring Bangladesh.

Thailand's largest oil company said on Wednesday it was preparing to send a tanker with $400,000 of fuel for the stricken city, where queues at filling stations stretched several kilometres (miles).

Electricity supplies are sporadic at the best of times, making many of Yangon's five million residents reliant on diesel-powered generators.

However, United Nations aid experts said much repair work still needed to be done at Yangon's port before any tanker can dock and start unloading fuel.

The power shortage is making water scarce in higher buildings because pumps are not working.