Donald Trump's nomination of loyalist Kash Patel for FBI director could be his most contentious yet.

Patel's widely considered controversial for his comments about shutting down the FBI headquarters and ceding all power to the President.

He's also spoken about coming after the media – and offering retribution to his enemies inside government.

US correspondent Richard Arnold told Mike Hosking one of the issues is the post isn't open – with current head Chris Wray still having more than three years left.

“Wray was appointed by Donald Trump during his first term, but their relationship soured early on. And then things worsened when the FBI issued that search warrant for classified documents.”

LISTEN ABOVE