A South Korean construction firm said Thursday it has signed a $7.25 billion preliminary agreement to build a new town in Iraq, terming it the biggest-ever single deal for a Korean builder overseas. Hanwha Engineering and Construction will build 100,000 homes plus infrastructure for the town 25 kilometres (16 miles) east of central Baghdad, a spokesman said. \"This is the largest single deal a South Korean construction firm has ever clinched overseas,\" he told AFP. The firm said a final contract with Iraq\'s National Investment Commission could be signed before December. Hanwha will be in charge of engineering, procurement and construction for the town, to occupy a 1,830-hectare (4,520 acre) site. Construction will take seven years, said the firm, an unlisted unit of the Hanwha Group. Last month Hanwha Engineering won a $1.2 billion deal to build a power station and desalination plant in western Saudi Arabia. In 2009 the builder secured a $750 million order from Saudi Arabia to build a power plant.