The Government's keeping its cards close to its chest - on how it'll fund a mammoth Defence splurge

It's injecting 12 billion dollars over four years, into building up our Defence Force workforce and equipment.

It's signalling it'll go into system upgrades, replacing helicopters- and enhancing maritime strike capability.

Defence Minister Judith Collins says the investment includes nine billion dollars on top of what we already spend on Defence.

She says it's a lot of money but there's no economic security without national security.