JAKARTA, Dec 4 (Reuters) - Indonesia’s government said on Friday the Japan Bank for International Cooperation had committed to invest $4 billion in the Southeast Asian country’s soon-to-be-launched sovereign wealth fund. The commitment was conveyed by JBIC Governor Tadashi Maeda in a meeting with an Indonesian delegation led by Coordinating Minister of Maritime Affairs and Investment Luhut Pandjaitan, according to a statement from the Indonesian embassy in Tokyo. Indonesian authorities have gone on overseas trips to promote the fund even before its launch, holding meetings with government financing arms and private equity firms like BlackRock and Carlyle Group. Last month, the government said the U.S. International Development Finance Corporation (DFC) had signed a letter of intent to invest $2 billion in the fund. Jakarta is currently finishing government regulations that would cement the formation of the fund, including one to allow the government to put in an initial $5 billion in cash and other state assets. Unlike traditional sovereign wealth funds, set up by wealthy countries to save oil revenues or foreign exchange reserves, the Indonesian fund and others in emerging markets aim to attract foreign firms as co-investors. Officials have said they intend to grow the fund to $15 billion and will use it to finance infrastructure projects and President Joko Widodo’s plan to relocate Indonesia’s capital to Borneo island from Jakarta. Indonesia would follow up the JBIC commitment by preparing the technical details, with the hope to realize the investment in the first quarter of 2021, the embassy said. The JBIC was not immediately available for comment. During the trip to Tokyo, Minister Luhut also held meetings with at least 20 potential Japanese investors in finance and energy sectors, according to the embassy statement. (Reporting by Fransiska Nangoy; Writing by Gayatri Suroyo; Editing by Alex Richardson and Catherine Evans)