HANOI (Yonhap News) ― Asian countries have emerged as the largest market for South Korean builders in recent months, data showed Tuesday, a sign that their efforts to diversify their businesses are paying off.

South Korean builders bagged a combined $6.36 billion worth of new orders in Asia in the first three months of this year, compared with $1.58 billion a year earlier.

The latest orders accounted for 68 percent of a combined $9.36 billion worth of overseas orders in the first quarter, according to the data compiled by the International Contractors Association of Korea.

Orders from oil-rich Middle Eastern countries stood at $2.46 billion in the cited period, down from $2.75 billion. For decades, the Middle East had been the largest market for South Korean builders.

South Korean construction firms clinched 291 orders in Vietnam out of 1,077 new orders in Asia.

GS Engineering & Construction Corp., South Korea’s fourth-largest builder, has won a $2.1 billion order to build the largest oil refinery and petrochemical plant in Vietnam along with SK Engineering & Construction Co.

The two South Korean builders will build the plant in Nghi Son, 200 kilometers south of Hanoi, by 2017 for Nghi Son Refinery & Petrochemical Limited Liability Co., according to GS E&C.

The largest plant in Vietnam, when completed, will be able to refine 200,000 barrels of crude oil per day, GS E&C said, adding it and SK E&C hold a 50 percent stake in the project.

Daelim Industrial Co., one of South Korea’s major builders, has launched a project to build a coal-powered plant worth $1.2 billion in Vietnam.

A consortium led by Daelim Industrial has also signed a $335 million order to build a thermal power plant in the southern part of Vietnam.

Under the contract with Cantho Thermal Power Company Ltd., a unit of Vietnam’s state-run electricity corporation EVN, the consortium will complete the power plant construction by October 2015, according to Daelim Industrial.

The construction of the power plant to be built in the O Mon district on the Mekong Delta will be farmed out to Japan’s Sojitz Corp., the South Korean builder said.

Daelim Industrial’s stake in the project is $285 million, the company said.

Daelim Industrial will design and construct the plant with a generating capacity of 330 megawatts of electricity, while its Japanese partner will supply steam turbines.

Hyundai Engineering and Construction Co. South Korea’s top builder, has also been building a five-star hotel and a residential and commercial complex in Hanoi.

Meanwhile, Keangnam Enterprises, a mid-sized builder, has clinched a deal to build a 72-story landmark building in Hanoi.

POSCO Engineering & Construction Co., a construction arm of South Korea’s largest steelmaker POSCO, has built the first department store in Ho Chi Minh City.