The Trinidad focussed oil and gas company, in a statement, said that Yan Liu made the decision to allow him to focus on other business interests.
It is effective immediately, and, in the interim, his role will be fulfilled by Mr Zhiwei (Kerry) Gu as his role will be temporarily extended to executive chairman.
Range also noted that its shares will be suspended from trading in Australia, as ASX listing rules require at two Australian resident directors. A recruitment process is presently underway. The AIM listing in London will remain unaffected.
"On behalf of the board, I would like to thank Yan for his contribution to the company and wish him every success in his future business ventures,” Zhiwei Gu said in a statement.
“Until a suitable CEO successor is appointed, I will step up to the role of executive chairman to lead the team and ensure that we remain focused on delivery of our objectives.
“We are working through the appointment process of a new director, and hope to resume trading on ASX in early 2019."