A proposed mega-council stretching 500km from Cape Palliser, the most southern point of the North Island, to the north of Wairoa has had a cool reception in Wairarapa and Wellington.
Such a council, proposed by the Hawke's Bay Regional Council, would have 11 members representing seven wards to cover 210,000 people, making it the fifth-largest in New Zealand.
The plan has been given final approval and was presented ot the Local Government Commission on Thursday.
Wellington Regional Council chair Fran Wilde says the proposal is a concern and the Hawke's Bay report does not explain what the benefits will be for Wairarapa.
Ms Wilde says Wairarapa has an important economic link to Wellington.
Masterton mayor Garry Daniell says Wairarapa's inclusion in the plan has come out of the blue.
Mr Daniell says while Hawke's Bay and Wairarapa have some similar interests, a single body for Wairarapa is still the best option.
Hawke's Bay Regional Council chairperson Fenton Wilson told Radio New Zealand's Morning Report programme on Thursday he is aware there will be criticism that the council has submitted the plan without consulting the public.
However, Mr Fenton said there will be time for all involved to have a say.