According to The Straits Times, Long Chong Provision Shop in Bukit Timah, for instance, is charging SGD2 for 10 eggs, up from SGD1.90. Another stall nearby, Feng Lai Provision Shop, also raised its price from SGD1.90 to SGD2.10.

At FairPrice stores, fresh eggs now cost between SGD1.75 and SGD5 for a pack, up from between SGD1.65 and SGD4.70 last week. From tomorrow, Prime Supermarket will raise prices for a box of 10 eggs by between five and 10 cents.

Importers said the price hike is mainly due to two chicken layer farms in Malaysia being suspended in March and last month from exporting eggs to Singapore.

According to the Agri-Food and Veterinary Authority (AVA), their eggs were found to have Salmonella enteritidis - a bacterium which causes food poisoning.

The two farms provided less than six per cent of Singapore's supply of 1.68 billion eggs last year. About three quarters were imported from Malaysia last year, with the rest produced locally.

There are currently 21 Malaysian chicken layer farms approved by the AVA.

Around four million eggs are imported daily from Malaysia. Industry players estimate that the daily supply fell by 30,000 eggs following the suspension of one of the farms last month.

Tan Lau Huah, chairman of the Eggs Import/Export Trading Association, said: "We had to raise prices in order to make up for the fall in supply.

The market prices of eggs from Malaysian suppliers also went up after the Hari Raya period." He said Malaysian suppliers also face increasing costs.

These include higher wages for drivers, costlier petrol and, since last Friday, higher Causeway toll charges.

Since two weeks ago, some importers have been getting surplus from other chicken layer farms in Malaysia to compensate for the drop in supply.

Tan Han Meng, who runs Meng Suppliers in Bukit Timah Market and Food Centre, has decided to maintain his egg prices for now.

He said: "It is okay as long as I do not make a loss. Egg prices rise and fall quite a lot. During school holidays when canteens are closed, supply goes up and prices fall."

Senior executive assistant Ng Bee Kheng, who buys about a dozen eggs every week, said prices are still manageable.

"I can still accept a change of one to five cents for an egg," said the 36-year-old mother of three. "After all, fresh eggs are something I must still buy even if they are costly; there are no alternatives or substitutes."

The impact is more acute for some eateries, such as Hatched in Holland Village. The cafe, which specialises in eggs, cooks up 30,000 each month.

Owner Gerald Tan told The Straits Times: "I get quite a sizeable quantity and one cent more for each egg translates to about SGD300 extra every month. We are absorbing this for now."