Chinese investors plan to develop a multibillion-dollar oil refinery in Batam, Riau Islands province, an official with the Office of the Coordinating Maritime Affairs and Investment Minister has said. Maritime and energy sovereignty deputy Purbaya Yudhi Sadhewa told an online press conference on Tuesday that the investors had sent a letter addressed to the Coordinating Minister’s Office, “asking for our agreement to support an investment worth around US$5 to $6 billion”.