Cabinet's being warned its window for a decision around replacing our two ageing warships is rapidly closing.  

An NZ Initiative research note says the frigates are set to retire within a decade and the complex geopolitical environment adds another layer of urgency. 

Retired Major General John Howard says we're seeing more volatility both in our region and at home.  

He told Ryan Bridge the country now has the option to think broadly about the maritime capabilities we want and how we defend our national interests.  

Howard says if we’re going to be serious about maintaining a blue-water capability, then we need a minimum of four warships. 

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