South Korea has completed the production of vacuum vessel sectors for the international thermonuclear experimental reactor project, aimed at achieving fusion power production at power plant scale, the science ministry said Friday.

The country has completed building four vacuum vessels for the ITER, the world's largest tokamak to be set up in southern France, according to the Ministry of Science and ICT.

A tokamak is a magnetic fusion device created to demonstrate the viability of fusion as a large-scale, carbon-free energy source, operating on the same principle that powers the sun.

South Korea is a member of the ITER consortium, launched in late 2006, along with the European Union, the United States, Russia, China, Japan and India.

The country is participating in the production of nine parts for the nuclear fusion device, including the vacuum vessel, the toroidal field conductor and thermal shields.

The vacuum vessels delivered by Seoul, each weighing about 400 tons, are core equipment for the ITER as they create an ultra-high vacuum environment for the plasma, acting as the primary confinement barrier for radioactivity.

Seoul was initially set to produce two out of the total nine vacuum vessels needed, but procured two more due to a delay in production by the EU, according to the ministry.

"Based on the core technologies and manufacturing capabilities for fusion reactors acquired through our participation in the ITER project, we will take the lead in the upcoming nuclear fusion reactor construction market and strengthen our global leadership," First Vice Science Minister Lee Chang-yune said. (Yonhap)