Christchurch Airport has just unveiled a ''new long-term proposal'' for a new airport in the Tarras region.

In a statement a short time ago, it said it is about to begin discussions on the potential of building a "world-class, sustainable airport" on 750 hectares of land near Tarras in Central Otago.

Chief executive Malcolm Johns says the concept would deliver widespread social and economic benefits to regions across the South Island.

"We've been creating social and economic outcomes for the South Island for generations. We now want to use our experience to ensure the South Island is well-positioned to take advantage of future aviation trends and remain well-connected to the rest of the world."

Johns says the airport team is pleased to have secured the land so it can begin discussions about its long-term thinking.

"Our top priority is a conversation with the people who live closest to the site – the Tarras community. This is their home and it's important they are given the opportunity to ask us their questions directly and understand our thinking."

He says the airport had planned to announce the proposal next week when he and other members of the project team will be in Central Otago.

"We've had to announce this early after a media inquiry. But our message to Tarras is we look forward to meeting you – we will sincerely listen to understand your ideas and concerns and we will factor your information into our thinking. We know airports work best alongside communities, not on top of them."

Johns says the project team will consult with people across the South Island.

"South Islanders are great at rolling up their sleeves and working together to get things done. We want to hear from those with ideas and feedback as we further investigate the feasibility of the project and shape its design.

"We have a lot of work to do, but our current concept is to start with a 2.2km, jet-capable runway. Building from scratch would enable us to design and build one of the world's most sustainable airports. Our plan is to build in modules so we can start small and grow to meet any future need."

Johns says $45 million has been spent on the project so far – which includes purchasing the land bordered by State Highways 8 and 8A.

"The expenditure was budgeted and will not impact on Christchurch Airport's operational dividends to shareholders."

Johns says Christchurch Airport has long seen the potential for a new airport in Central Otago.

"We're an intergenerational company that has long seen the potential of a new airport in Central Otago. This would be make a real difference to future generations of South Islanders.

"This site is close to existing infrastructure and is easily accessible for a number of regions. Its topography would enable airlines to use their most sustainable aircraft.

Central Otago Mayor Tim Cadogan this afternoon said it was a surprising announcement and "big news for the community".

"Christchurch Airport has signalled in a media release this afternoon that they are taking a long-term approach and their top priority is having conversations with and working alongside the community. This is very early days in what will be a very long process. At this early stage I encourage all our community to get informed and get engaged in the process and form their own view."

CODC chief executive Sanchia Jacobs said her executive team had just learned of the news today.

"As a consenting authority, we don't have a view on this but will be watching with interest and in the event an application is made for consent we will follow the statutory process."