South Korea's largest business group Samsung signed an initial deal Wednesday to invest $7.04 billion in a state project to build a green energy complex on reclaimed wetland.

Samsung signed a memorandum of understanding with the government to spend 7.6 trillion won ($7.04 billion) on the construction of eco-friendly production facilities from 2021, the prime minister's office said.

The government will provide full administrative support plus a plot at the reclaimed Saemangeum wetland area on the west coast, about 200 kilometres (125 miles) south of Seoul.

Samsung said its green-energy development would have a wind-power generator, a production base for solar batteries, a research institute and houses for about 20,000 workers.

It said the investment was in line with its announcement last year to spend about 23 trillion won on new growth engines such as health care and green energy over the coming decade.

Samsung's investment is expected to speed up the massive government project to turn the reclaimed area into an eco-friendly town with industrial, tourism and agricultural facilities as well as science and research institutes.

The reclamation included the building of a 33.9 kilometre (20 mile) sea dike, which was completed in 2006.

Last August OCI, South Korea's leading maker of polysilicon used in solar panel cells, announced a plan to invest some 10 trillion won in the area by 2020.