South Korea has placed a temporary ban on imports of oranges from California, citing contagious fungi found on the fruit.

The Agriculture Ministry's National Plant Quarantine Service imposed the ban on oranges produced in California's Tulare and Fresno counties.

The two counties supplied 84 percent of South Korea's orange imports last year, totaling 145,000 tons.

Quarantine authorities said oranges from the two counties were found to be contaminated by a fungi called "Septoria citri".

Officials said the fungi posed a threat to the tangerines and other citrus fruits grown in Korea's southern coastal areas that are a main source of income in the region.