The cost of the Government's new Cook Strait ferries is still unknown - but ACT's David Seymour has offered up some clarity. 

On social media, David Seymour said it'd cost 'approximately half' of Labour's proposal - which was projected to be between three and four billion dollars. 

But Winston Peters says that's not accurate. 

Seymour says people have taken his words too literally. 

"When I said half, what I meant is - it's going to be a lot less, like when someone says it's half the price. Often, they don't literally mean half, they mean it's just a lot less, and that's what it will be."

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