A New Zealander who's had a key role in the Trump Administration says it's been a challenging, but rewarding four years.

Chris Liddell is one of the few people in top White House positions who've stayed the distance, apart from Trump family members.

The Deputy Chief of Staff has been nominated to become Secretary-General of the OECD.

Liddell told Mike Hosking the last four years have been worth the ride, but hasn't been without its costs.

“I have always wanted to be a player, rather than a spectator, and I want to make a difference to the world.”

Preparations are going on for a transition in the White House.

Donald Trump is still contesting President-elect Joe Biden's win in the courts.

Liddell says there will be a transition one way or the other.

He says the legal challenges have got in the way of some of the formal aspects of a transition, but there's a lot happening informally behind the scenes.

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