Coca-Cola Co., the world's biggest soft-drink maker, said its bottled-water plants in Japan are running 24 hours a day to meet demand amid fears of tap water contamination from the crippled Fukushima No. 1 nuclear plant.

"The irradiated water scare affects every part of Japan," Kei Sakaguchi, a spokesman for Coca-Cola (Japan) Co., said Wednesday. "We're making a full assessment of our product schedule and gave priority" to some products, including water and tea, he said.

Companies including Coca-Cola, Fast Retailing Co. and Toyota Motor Corp. are trying to lessen disruptions of supply to survivors of the March 11 earthquake, the strongest on record to hit Japan, and devastating tsunami. The government last week asked beverage makers to increase production of bottled water after revelations of rising contamination in water and food supplies triggered bulk buying.

Coca-Cola may import 1 million cases of mineral water from South Korea this weekend to meet demand in the Tohoku region, as well as Tokyo and its surrounding regions, Sakaguchi said. Suntory Holdings Ltd. and Kirin Holdings Co. also said they boosted orders for imported water.

Coca-Cola, Japan's second-biggest bottled-water maker by market share, has 28 plants operated by 12 bottlers in Japan and seven of them produce water, according to Sakaguchi.