Judith Collins is defending her comments about prominent microbiologist Siouxsie Wiles.

The Auckland University Covid expert has faced criticism for taking her mask off, while she and a bubble mate were alone on an Auckland beach.

But Collins has also come in for criticism, for calling Wiles a "big fat hypocrite".

The National leader told Mike Hosking she wasn't referring to Wiles' weight, and the controversy is politically-motivated.

“Sometimes when you tell the truth about something that’s happened, when it’s someone like Siouxsie Wiles or someone else that they’ve decided that they love, you’re going to get a backlash.”

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