Labour would consider public-private partnerships or Chinese investment to fund much-needed infrastructure, leader Andrew Little says.
Mr Little was hitting back at Prime Minister Bill English's claims Labour wants to slow the economy because it is unwilling to spend on infrastructure to keep up with growth.
Mr English made the comments ahead of Thursday's Budget.
"We're not going down the line of the opposition parties of saying, 'well, let's stop the economy growing because it's too hard to keep up'," Mr English said.
"We want to keep up, and sort different sources of finance, different models of financing are all going to be part of how we make those investments over the next five years."
However, Mr Little said Labour had committed to the city rail link and light rail to the airport in Auckland, and light rail in Chrisrchurch, but there was still a massive shortfall in infrastructure requirements.
He told Morning Report's Susie Ferguson Labour would look at creative ways of funding what else was needed.
Asked if that was public-private partnership, he said, "Given the shortfall that we've got, and the urgency with which we have to get some of that work under way, we've got to keep an open mind to everything - to every possibility," Mr Little said.
"I've long seen and long studied public private partnerships. There are some that have been absolute disasters and some that have actually been quite successful.
Mr Little said he also would not rule out overseas investments, including from China.
"I wouldn't rule anything out. The conditions have to be right, it has to be something in it for us as well, it wouldn't be anything as holus bolus as sign-off to a private overseas investor and say 'you do this'.
"We'd have to make sure we're working on our own internal skills, our own workforce, building up our own capability and capacity to do things.
"But you can do that with foreign investment as much as local investment."
He said he thought it was embarrassing for Mr English to have made the claim that Labour wanted to slow the economy, and that National had held Auckland back from growing and developing its own prosperity.
However, he would not give a figure on how much Labour would spend on infrastructure.