Jacinda Ardern has let rip at National over their soon to be released ad campaign ridiculing Labour's tax policies, describing them as "desperate" liars.
Speaking in Nelson just a few hours after the National ad campaign was released this morning, Ms Ardern said the National ad campaign "Let's tax this", a play on Labour's campaign motto "Let's do this", was blatant "scarmongering".
"I've seen a further ad today that is full of lies and scaremongering," Ms Ardern said.
"I will run an open, relentlessly positive campaign but they need to start running an honest one.
Ms Ardern also quickly dismissed suggestions her strong reaction to National's ad campaign was to do with last night's poll which had National 10 points ahead of Labour.
"It's to do with the ads, the ongoing lies the mis-truth and the desperation," she said.
"We've already ruled out a number of taxes that they [National] continue to claim we'll introduce.
"In the ad they released today they claimed we were increasing income tax. That is patently incorrect."
National's negative tax video will soon be running on TV and online with the message that a Labour government could impose at least six new taxes which would stall the economy.
The ad release comes as National was boosted by yesterday's poll, putting the party 10 points ahead of Labour, and the belief it's finally getting the upper hand in the election campaign.
In launching the video, ad campaign manager finance spokesperson Steven Joyce praised New Zealand's existing tax system.
"New Zealand currently has a broad-based, fair tax system," Mr Joyce said.
"We simply don't need to impose a capital gains tax, land tax, regional fuel tax, extra income tax, water tax or an inheritance tax."
Labour has said it will set up a tax working group if it wins the election and then decide which of its recommendations to implement.
Ms Ardern has said a capital gains tax wouldn't include the family home or the land it's on.
She has also said Labour won't increase income tax.
A Newshub Reid Research poll released last night carried a shock result - National had gained four points to 47.3 per cent while Labour had slipped to 37.8 per cent.
It's being interpreted as an indication voters are starting to think about Labour's policies rather than its new leader, and are becoming concerned about unspecified taxes that could be implemented if there's a change of government.
Previous 1 NEWS Colmar Brunton polls have shown Labour in the lead.