Labour leader David Shearer said Parekura Horomia's death came faster than expected and the party is mourning the loss of an enormous presence.
Mr Horomia died on Monday at his home at Mangatuna near Tolaga Bay surrounded by his whanau. He was 62.
The Labour MP held the seat of Ikaroa-Rawhiti and was Minister of Maori Affairs from 2000-2008.
His body will lie at Hauiti Marae in Tologa Bay, where more than 1000 mourners are expected to visit to pay their respects this week before his burial on Saturday morning.
David Shearer and his caucus will arrive at the marae on Wednesday to pay their respects, while Prime Minister John Key will travel there with his National Party caucus on Friday.
Mr Shearer is returning from Washington and told Radio New Zealand's Morning Report programme on Tuesday he knew that Parekura Horomia was unwell, but his death was unexpected.
Mr Shearer said Mr Horomia gave good advice when he was appointed Labour leader, had a large work ethic and was always welcome onto the marae where ever he was throughout New Zealand.
Former Prime Minister Helen Clark said she has never worked with a better human being than Parekura Horomia, describing him as a kind man with a big heart.
Miss Clark is now working for the United Nations in New York and said Mr Horomia achieved several milestones for Maoridom, including lowering Maori unemployment and lobbying for better indigenous representation on television and radio.
She told Morning Report she values the work Mr Horomia did when she was Prime Minister and said he took great pride in Maori education and the number of Maori students who graduated from university with PhDs.
A 'gentle giant' and 'special mate'
The Prime Minister said Parekura Horomia was genuinely liked by MPs from across the political spectrum.
John Key said Mr Horomia stood up for his people as Maori Affairs Minister and the Government has enormous respect for his tireless work.
"He was also a very hard-working MP and represented the people of his electorate extremely well. My view of Parekura Horomia is that he's one of the genuine MPs that is liked on all sides of the House and by all political parties. He was a real gentle giant and I think we'll miss him."
Maori Party co-leader Tariana Turia said she has lost a great friend and confidant. Mrs Turia knew Mr Horomia before they entered Parliament as Labour MPs, and despite her departure from that party, said he was her "special mate" through thick and thin.
United Future leader Peter Dunne said Mr Horomia was a man who exuded leadership and his legacy is one of language, education and employment advances for Maori.
"He always gave off every sense of listening very closely to what people were saying and being very thoughtful about them.
"I just think this is a man who exuded leadership, he exuded a sense of warmth and friendship, and he'll be a huge loss to his whanau, his people, his electorate, his party - but also to the country."
Green Party co-leader Metiria Turei said New Zealand is a lesser place for his passing, but his achievements including the creation of Maori Television will live on.
New Zealand First leader Winston Peters said Mr Horomia was calm and reasonable, even when he was unjustly criticised. He said he was well liked and his colleagues will miss him greatly.