Nine News Political Editor Chris Ulhmann says Christian Porter’s resignation as a cabinet minster was inevitable once there were concerns over the funding of his legal fees.

Mr Porter resigned from his portfolio as Industry, Science and Technology Minister on Sunday as pressure mounted for him to reveal who had funded his legal defence.

Uhlmann says the resignation was inevitable once it was revealed how the legal fund was set up

“It was (inevitable), and it wasn’t over the initial event, it really was over … the way that legal fund was set up; a blind trust, mystery donors,” he told Gary Adshead filling in for Liam Bartlett on 6PR Mornings.

“The minister can’t accept money from sources that are unknown.”

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