While the NZ Greens prepare the way for the restoration of deposit insurance, they are also promising to recapitalise the state-owned Kiwibank.Greens co-leader James Shaw says he views the bank as a "strategic asset" and would endeavour to put it on a more competitive footing to take on the Australian-owned banks in New Zealand."We want to scale it up to be more of a commercial operation to compete against the major banks," Shaw said."In my view Kiwibank is a strategic asset - it's important to have at least one New Zealand-owned bank operating in this market."Although the New Zealand Labour Party (the Green's potential coalition partner) has been silent on what it plans to do with Kiwibank, Shaw said the Greens would push for a NZ$100 million recapitalisation."It's one of those policies we would hope to persuade Labour on through evidence and reasoning," he said.Shaw said the Greens' proposal was conditional on the next government providing an iron-clad guarantee to keep the business state-owned.Last year the National government directed NZ Post to sell down part of its shareholding in the bank to other state-run entities, including the NZ Superannuation Fund.Under the arrangement, the NZSF is allowed to offload its stake after five years, with the government holding first rights to buy back the interest.Shaw says the move has altered the destiny of Kiwibank and will likely see the country's fifth largest deposit-taker sold to a foreign institution in 2021."The job of a super fund is to maximise returns," he said."If Kiwibank continues to grow and its net asset base increases in value no future finance minister worth their salt is going to agree to buy it back."Shaw said the Greens were open to the idea of a national banking inquiry proposed by rival minor party, New Zealand First.Also, he would not rule out the possibility of introducing a special levy on the Australian-owned banks to address concerns over money flowing out of New Zealand in the form of banking profits.However, the party's policy focus was on structural reform of the industry."That [a levy] is something you've got to keep in your pocket," he said. "We're just not looking at it now.""I'm more interested in looking at the structure of the banking industry and the issue of New Zealand ownership."