A $40 million expansion of Christchurch Airport's freight capacity will help to unlock more economic growth in the South Island, Prime Minister Christopher Luxon says.The airport has doubled its freight handling capability with up to eight cargo planes now able to park at any one time.The freight apron was now bigger than six rugby fields and contained enough concrete to fill 35 Boeing 767s.Luxon, who formally opened the apron at a ceremony on Thursday morning, said the South Island had massive economic momentum and was leading New Zealand out of its downturn."If we could turn the rest of New Zealand into Canterbury it would be fantastic," Luxon said."It's a fantastic place and we want the South Island to continue to grow and continue to have that real momentum."Luxon also toured DHL's freight warehouse and cut the ribbon for the freight apron."This is an outstanding and critical piece of infrastructure for New Zealand," he said."We need this airport to unlock the growth that sits in the South Island."This region is doing exceptionally well, it's got massive amounts of momentum and we just want to get in behind you and encourage you to go for even more ambition, more aspiration, more positivity, more can-do and having a gateway like this that actually connects the South Island out to the world is just so critically important to New Zealand."You are leading the charge."Christchurch Airport chief executive Justin Watson said the airport had also built future capacity and growth into its plans."Why did we build it? Because the way people shop, the way businesses move products has changed and its changed rapidly since Covid. E-commerce has grown rapidly and customers expect faster delivery than ever before. This expanded apron with direct airside access is our response," he said.DHL would soon be joined by FedEx at the campus.