"This was an act of lunacy by a lunatic."
Little said the document was meaningless as he had been on a public road - State Highway 2 - and it would not stop him returning to the area.
"I expect to be back in the region fairly soon actually. I'm not going to be put off by the actions of a lone actor."
Police confirmed they were aware of the matter and were making enquiries.
Little said he would make a statement to them in the next few days.
Ngai Tamahaua - a division of eastern Bay of Plenty iwi Whakatōhea - issued a media release claiming responsibility on Tuesday.
Hapū deputy chair Tim Herewini told RNZ one of its members took action in protest over the minister's handling of their Treaty negotiations.
"The reason [Mr Little] has been trespassed is because he is an existential threat to the sovereignty of the hapū and to our survival and to our future."
Herewini would not confirm who had served the notice, but insisted they had been "officially authorised" by the hapū.
"The operation was done very carefully, very professionally, with safety in mind ... and it was conducted very courteously as well."
He said Little had previously been warned not to come into their rohe, or territory, and to ignore that was a "provocative act".
"The minister had been informed well in advance that if he did try to do this, or any of his officials did, that he would be intercepted at the earliest opportunity, trespassed and then escorted out."
The dispute centres on who is mandated from Whakatōhea to negotiate its Treaty settlement with the government.
A Waitangi Tribunal report last year ruled the Crown had unfairly negotiated a $100 million deal in principle with a group that did not have the backing of the whole iwi.
The Crown recognises Whakatōhea Pre-Settlement Claims Trust, but Ngai Tamahaua and other hapū reject the trust's mandate and accuse Mr Little of trying to steamroll ahead.
The Waitangi Tribunal has since launched an inquiry into the historical grievances of Whakatōhea.
Former Whakatōhea trust board chair and treaty claim negotiator Tuariki Delamere said he also had concerns about the settlement process, but Ngai Tamahaua's actions went too far.
"In these days of worldwide terrorism threat, to have someone drive up on a ministerial car and cut them off is totally inappropriate," he said.
"We're not that far from a situation where ministers could well have armed police with them and you could have a shooting match."
Little said the latest action would not dissuade him from working with Whakatōhea to resolve its internal conflicts.
"It's not unusual for there to be elements within an iwi who disagree. What I do know of this person is he doesn't represent anybody - he represents himself. My job is to deal with iwi and hapū, not individuals."
- RNZ