Ms Long, who has most recently been joint managing director and finance director of Investa Property Group and previously was group chief financial officer, is replacing Toby Phelps who has returned to Britain.

Ms Long will join Mirvac's chief executive Susan Lloyd-Hurwitz as one of the many leading female directors in property.

Ms Long has almost 20 years of financial management experience and has been with IPG for almost 10 years.

"I am very happy to be appointed to the role, but given my involvement at IPG, it will be a seamless transition. However, I have resigned from my other roles at Investa to avoid any conflicts of interest."

Campbell Hanan, chief executive of Investa Office said: "Ming has been involved with IOF as an executive director since Investa took over management of the fund in 2011. She has a deep understanding of IOF's assets and capital structure and was the stand-out choice for the role."

Mr Hanan said Ms Long was chosen after a wide search of internal and external candidates.

He added that any internalisation of the office fund, would be a separate decision and Ms Long's internal appointment was not a reflection that any corporate activity was imminent.

Jonathan Callaghan, who has been appointed managing director and finance director of IPG, will replace Ms Long on the IOF board as an executive director.

He has more than 17 years legal and corporate development experience and has been with Investa for eight years.