Mitsubishi is to fund up to $2.25bn to develop an Indonesian LNG plant, to be commissioned by the government.
Under an initial agreement, Mitsubishi will own a 51% stake in PT Donggi Senoro LNG, which will build and operate the LNG plant. State oil and gas firm PT Pertamina holds 29% and PT Medco Energy International the remaining 20%.
The project will supply each of the Japanese power companies, Kansai and Chubu Power, 1 million tonnes a year of LNG for 12 years from 2012.
The LNG plant is to be built near the Donggi and Senoro gas fields in Central Sulawesi.
Mitsubishi has put forward its plans to fund the project expecting that the government will go ahead with the initial proposals.