Mr Key's decision followed controversy about whether to invite him at all followed by an attempt by the marae to say he could not speak on political issues. The PM said that amounted to a gag and prevented him responding to claims of the expected TPP protesters.
Mr Little said it was disappointing the Prime Minister was not able to speak at Waitangi on a day put aside for such debate. "Some people are concerned about contemporary issues and I think it is a mark of leadership for him to make himself available, notwithstanding the conflicting information he seems to be getting about speaking rights."
Mr Little said he could understand the frustration Mr Key felt about the changing rules, saying it would be difficult to speak on such a day without veering near politics.
The letter that set out the request not to discuss politics said the same rule would apply to other parties - a rule that was confirmed by marae trustee Emma Gibbs.
However, Mr Little said no such rule had been communicated to him. He would assess for himself what he could say after talking to the marae elders today.
Mr Key's decision means no other ministers will go on to the marae for the scheduled 10am Government powhiri, although it is possible some National MPs still will.
Many ministers were already at Waitangi yesterday for the launch of the Northland economic development plan. Iwi leaders had also arrived for the usual meetings with the Prime Minister and ministers.
Ngai Tahu leader Sir Mark Solomon would not comment on Mr Key's decision, beyond saying it was up to him. As well as the iwi leaders' talks, Mr Key, who is also Tourism Minister, will miss the opening of the new Waitangi Museum and his annual Waitangi breakfast.
Maori Party co-leader Te Ururoa Flavell said he would not go to Te Tii today. He had already been welcomed onto the marae yesterday morning - prompting marae elder Kingi Taurua to accuse him of being a "slave to the National Party".
Mr Key also said he was concerned some of the marae elders were encouraging violence.
"I can't go and I won't go to Waitangi with a gagging order on me and I won't go when there is a position where senior elders of that marae are actively encouraging I think violence actually, and that is what Kingi [Taurua] is putting out there."
Mr Taurua said he had encouraged the protesters, but had not incited violence.
"I'm hurt by that. I'm not inciting violence, I'm only encouraging people to protest about the policies."
Responses at the marae were mixed.
Ngapuhi leader Rudy Taylor said he was disappointed by the Prime Minister's decision but understood the reasons.
Mr Taylor is the co-chair of Te Kotahitanga, one of the groups involved in trying to resolve the mandate for the Ngapuhi settlement. He hoped Mr Key reconsidered.