Wellington, Dec 18 NZPA - If Wanganui adopts two acceptable spellings, people will drift towards Whanganui, says Maori Party co-leader Tariana Turia.

Land Information Minister Maurice Williamson will announce his decision on the controversial "H-bomb" issue in Wanganui at 11.30am.

After lobbying by local Maori, the New Zealand Geographic Board decided earlier this year the spelling should be changed to the Maori version, Whanganui, but locals voted four to one against.

One option could see both spellings acceptable, similar to Aorangi/Mt Cook and Mt Egmont/Mt Taranaki.

Mr Williamson's decision may see government agencies have to use the "h" but others would have a choice.

Maori Party co-leader Tariana Turia said she would prefer Mr Williamson to do the right thing and spell it with an "h", as that was the correct spelling. She acknowledged the feelings of the wider community had to be taken into account.

However, if it was to be spelled both ways she believed that over time most people would spell it Whanganui.

"We already have a lot of non-Maori in the community who do use the `h'. It's on the river, it's in the DHB, it's in the polytech and there are other tourism organisations who do use the `h'. I think it's just a stage process, and people, by osmosis, will change," she told Radio New Zealand.

Wanganui Mayor Michael Laws, a vehement advocate for retaining the current spelling, said the people of Wanganui did not want the "h".

"Obviously it is the desire of Wanganui people that their democratic decision -- made by referenda in both 2006 and 2009 -- is upheld."

Mr Laws said the council left no stone unturned in its efforts to retain the name.

"We believe the NZ Geographic Board to be wrong in both fact and logic."