Maori Party MP Hone Hawawira says the solution to the Foreshore and Seabed Act would be to put the foreshore and seabed under Maori control but make it inalienable and guarantee access for all.

"Make it inalienable so it can never be sold - not just to Maori and Pakeha, but overseas people who are buying up big chunks," he said, addressing a hikoi of around 200 people at the flagstaff below Te Whare Runanga.

He said there would be times when beach access would be denied because of rahui (a ban on fishing) and tangihanga but that would apply to Maori as well.

Mr Harawira said he was "not fussed" that the flag was not flying today alongside the Union Jack, the New Zealand flag and the United Tribes flag.

"If it was, I wouldn't be marching."

He described the Maori flag as being similar to "Pantene shampoo".

"Getting it up on the pole may not happen overnight, but it will happen," he said.

He said the flag issue was a reminder to Maori that there was still a lot of work to do and cited the Foreshore and Seabed Act as an example.

He warned the crowd to be sceptical, citing Prime Minister John Key's earlier message to the country: "Let's be realistic."

"Whenever a politician says to Maori 'Let's be realistic', that means: No."

Mr Harawira joined around 200 protesters who marched onto the treaty grounds this afternoon.

Many carried the Tino Rangatiratanga flag - also known as the Maori flag - and chanted the "kamate kamate" haka along with "hikoi, hikoi" and "Tino Rangatingara", or self determination.

They burst into a spontaneous haka before continuing on to Te Whare Runanga.