SEOUL (Bloomberg) -- South Korea's industrial output probably expanded at the fastest pace in three months in April, stoked by increased overseas shipments.

Manufacturing production advanced 1 percent from March, when it fell 0.4 percent, according to the median estimate in a Bloomberg News survey of 11 economists.

Strengthening global demand is boosting sales for companies including Hyundai Heavy Industries Co., whose orders in April rose 0.7 percent to $1.18 billion. Exports, which account for about 40 percent of gross domestic product, are helping extend the nation's longest economic expansion in a decade. “Production rose mainly on the back of rising exports,” said Lee Sung Kwon, chief economist at Good Morning Shinhan Securities Co. in Seoul. “Consumer demand seems to have bottomed and entered a modest recovery phase.”

Asia's third-largest economy grew 0.9 percent in the first quarter from the previous three months, spurred by rising exports and a pickup in consumer spending. That marked a 16th consecutive quarter of expansion, the longest stretch of growth since the 17 quarters ended December 1996.

The Organization for Economic Cooperation and Development last week raised its 2008 economic growth forecast for South Korea, saying stronger demand for the nation's exports, led by China, will spur expansion.

South Korea's economy will expand 4.8 percent next year after growing 4.3 percent this year, the OECD said on May 24.

“Even though it's gradual, there are some positive signs the economy is improving,” Finance Minister Kwon Okyu told reporters on May 14. -------------Exports surge

Exports surged 17.8 percent in April from a year earlier, the largest gain in three months, adding to signs growth may accelerate. Increased shipments to China and Europe are helping the nation weather a slowdown in U.S. demand.

Among signs domestic demand may be picking up pace, South Korea's consumers become more confident than at any time in the past year in April. An index of consumer sentiment rose to 100.1 from 97.8 in March, a report showed on May 10.

Industrial output climbed 5.3 percent in April from a year earlier, according to the survey of economists. That's faster than the 3.1 percent annual gain in March.