National has been engaged in a barrage of negative ads about Labour in recent weeks, and they're not backing down despite the claims copping backlash.

Some clips describe tax ideas from other parties - like Opportunity’s Land Tax or the Green Party’s capital acquisition tax - as 'Labour's taxes'.

National Party campaign chief Simeon Brown is on the defence - and says there's an issue of credibility impacting Chris Hipkins and Labour. 

"They've done it before, they've got a track record of saying one thing and then bringing in more taxes - and that was at a time when they won the election with a Labour-majority Government."

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