Matamata-born Liddell rose up the ranks to become chief executive of New Zealand company Carter Holt Harvey in the 1990s, before he relocated to the United States.
In 2005 he was appointed chief financial officer of Microsoft, then shifted to General Motors where he helped the company recover after the global financial crisis.
At the start of this year he was named Trump's White House director of strategic initiatives - a job placing the New Zealander at the head of a group dubbed "the White House think tank".
Liddell had joined Trump's administration in early 2017 and had worked closely with Jared Kushner, the president's son-in-law and senior advisor, since his appointment.
His role included assessing the way the Government bought technology, and the services it offered people online.
With a lineup of high-powered jobs within big global corporates, Liddell had the sort of experience that would fulfil Trump's hopes for someone to fill the role, insiders thought.
In a television interview late last year, Liddell said he expected people would see a more moderate Donald Trump presidency "than the one seen on the campaign trail."
"People focus on the President, as they should, because the President's the single most important person," he had told TVNZ.
"But the President works through these huge numbers of other people running various departments and so forth, so who he starts to surround himself, how he manages those people, will define his success."
