NT could reject NDIS, follow WA

The Northern Territory has vowed it will reject the full national disability insurance scheme if its trials fail.

There are concerns the NT is being sold a dud by the federal government with more than half of territorians in the Barkly region trial failing to qualify for the $22 billion scheme.

The NT government looks set to be forced to spend another $20 million to keep supporting those outside the scheme, resulting in two separate disability groups.

That's not good enough for the chief minister.

"If the NDIS isn't working for the territory, we won't sign up to it," Adam Giles told reporters in Darwin on Tuesday.

Instead, the NT could follow Western Australia's alternative MyWay model to get better service delivery with less money, starting with a potential second trial site.

"That could be the best way to go ahead in the future," Mr Giles said.

Assistant Social Services Minister Mitch Fifield said he visited Tennant Creek last month and the scheme was having a positive effect.

"But I am aware that we may need to do some things differently in remote areas," he told AAP.

"I never want to let design elegance get in the way of practical outcomes."

Meanwhile, 2000 children and young people in NSW will get access to the scheme a year early.

The $20 million agreement between the state and commonwealth signed on Tuesday will fund support for residents in the Nepean and Blue Mountains regions.

About 11,000 participants are accessing the NDIS in seven trial sites around the country.

That will be ramped up to 460,000 from the middle of next year through to 2018-19 when the scheme is rolled out in full.