A former Prime Minister believes National's been tightening the purse strings for too long.

Sir Geoffrey Palmer thinks there's a mood for political change.

 He told Rachel Smalley Bill English's party is making a lot of promises about spending this election.

But that's after running a very tight ship for many years.

"And they kept that on for too long and they are now paying the price for that."

Palmer also spoke in defence of Jacinda Ardern, who's been criticised in some quarters for not having enough experience to potentially lead the country, saying inexperience isn't a factor.

He said there are enough other senior and experienced politicians in the party to assist.

"When David Lange and I came in neither of us had had any experience in government before and we found it quite easy to run the government and take decisions."

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