"He will write a letter of resignation as soon as possible this week," Djadjuk Natsir, Kirana's private secretary, noted in Kuala Lumpur on Wednesday.
Natsir remarked that Kirana will hand over the letter of resignation to PKB General Chairman Muhaimin Iskandar or another executive board member.
Kirana was inaugurated as Indonesian ambassador to Malaysia on May 18, 2017. He will demit office on May 18, 2020.
Kirana had earlier resigned as the party’s deputy general chairman for the 2014-2019 period when President Joko Widodo (Jokowi) inaugurated him as member of the president's advisory council in 2015.
Kirana, concurrently founder of the Lion Air Group, also resigned as the airline company's CEO.
Kirana confirmed a plan to quit as a PKB member.
"It is true that I quit as a PKB member," he added.
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