A group building what will be the world’s largest and most advanced optical telescope atop Mauna Kea says the Japanese government has allocated key funding for the construction of the project.

The Thirty Meter Telescope said Wednesday the Japanese parliament last month approved a budget including more than $12 million for the telescope.

TMT says Japan is expected to manufacture the main telescope structure and the mirror blanks for the segmented primary mirror. In total, Japan is expected to fund one-fourth of the total cost of construction.

The telescope is being built by a group including the California Institute of Technology, the University of California and the Association of Canadian Universities for Research in Astronomy. Government-supported observatories and scientists in China, India and Japan are also participating.