The Northern Territory government has lifted speed restrictions from another section of its highway network in a move designed to "give responsibility back to motorists".

The de-restrcicted 60km section of the Stuart Highway between the townships of Alice Springs and Ali Curung extends the Territory's open speed limits network to 300km worth of highway.

The additional section, which is open from Friday, follows a $3.1 million investment in road works, along with extensive trials which suggest raising the speed limits can help reduce road fatalities.

Northern Territory chief minister Adam Giles cited extensive research which showed a reduction in road deaths when open speed limits were in place.

A 300km section of the Stuart Highway in the Northern Territory now features open speed limits. Photo: Supplied.

"Territorians have always acted sensibly in open speed limit zones, with 85 per cent of drivers travelling between 133-139km/h; and most driving to the conditions," the minister said.

"Of the 11 crashes that occurred during the 2014 year-long trial period on stretches of the Stuart Highway, there were no fatalities. And of the one serious injury reported, alcohol and not wearing a seatbelt were factors.

"The Territory has a unique road network, and we'll continue to expand, upgrade, and take an evidence-based approach to speed limits on our major highways."

In enabling the de-restriceted area, NT authorities cleared trees away from the edge of the highway, widened curves and improved marking and signage.

Giles said his Country Liberals Party intended to continue extending the open speed limits network as far as Katherine, some 1200km north of the Alice Springs starting point. The government is also investigating the de-restriction of the Barkley Highway, which runs east from outside Tennant Creek to Avon Downs, on the Northern Territory-Queensland border.

The latest extension has drawn criticism from road safety and medical authorities, however the government remains resolute in its position.

A recent report commissioned by the government found the fastest speed admitted to by a driver on derestricted roads was 295km/h. Prior to open speed limits being allowed, the average speed in the trial area was 134km/h, with the highest speed registered at 205km/h.

Open speed limits were abolished by the former Territory Labor Government in 2006 and replaced by a maximum limit of 130km/h. More people died on Territory roads (307) in the six years after than in the six years before the change (292).

Moreover, countries such as Germany, the Netherlands, Spain and Denmark record lower annual road traffic deaths than Australia despite featuring speed limits of 130km/h or higher.

The Northern Territory case study has prompted the NSW government to consider raising the speed limit on the Hume and Pacific Highways, though there has been no recent developments on this.

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