BRUSSELS, Oct. 24 (Xinhua) -- The International Thermonuclear Experimental Reactor (ITER), a landmark multinational fusion energy project involving the European Union (EU), got started on Wednesday, the European Commission announced here.

The ITER agreement, signed on Nov. 26, 2006, entered into force30 days after the last ratification, which was by China, the commission said in a statement.

ITER has been the largest ever scientific research program under multinational collaboration, aimed at developing a sustained solution to energy production.

An international ITER Organization, set up by the ITER agreement, is responsible for the construction and operation of an experimental reactor which will reproduce fusion, a physical reaction that occurs in the sun and stars.

The 11 billion-euro project involves the EU, China, the United States, India, South Korea, Russia, and Japan, representing over half of the world's population.

Among its members, the EU will pay 45.4 percent of the total ITER budget, while China is responsible for 9.1 percent of the budget, which is equal to the percentage shared by each of the other five participating countries.