The Government says there will be downsides to loosening restrictions on heavy vehicles.

Trucking lobby group Transporting New Zealand is calling for weight restrictions to loosen immediately, not just in Phase Two of the fuel response.

Finance Minister Nicola Willis says the Government's looking into options they can implement quickly - and they're weighing up the benefits and drawbacks.

"I wouldn't rule out progressing them in Phase One, because actually, what they'll do is reduce the cost of fuel for major diesel users."  

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