The flag carriers of New Zealand and China on Monday detailed plans for an alliance that would reinstate direct flights between Auckland and Beijing by the end of the year.

The alliance, subject to regulatory approvals, would see Air China introduce a daily direct service between the two cities, while continuing to codeshare on Air New Zealand's daily Shanghai- Auckland service.

The airlines said in a joint statement that they aimed to almost double their capacity between China and New Zealand while delivering greater frequency and network connections.

Air New Zealand Chief Executive Officer Christopher Luxon said the alliance would see two home carriers with complementary strengths at each end of the route working together to drive traffic in both directions.

"By connecting the Chinese capital with New Zealand again we would provide tourists and business travelers with unparalleled air connectivity between and within each home market," Luxon said in a statement.

Air China Chief Executive Officer Song Zhiyong said the relationship between China and New Zealand was entering into a new phase with significant achievements already made in economic development, as well as cultural and political exchanges in recent years.

"The proposed alliance with Air New Zealand allows both flag carriers to build a sustainable air service between Beijing and Auckland and supplement the existing connectivity between China and New Zealand," Song said in the statement.

Auckland Airport estimated the Auckland-Beijing daily service would contribute an additional 200 million NZ dollars (152.55 million U.S. dollars) a year in tourist spending to the New Zealand economy.

"Overall Chinese passenger arrivals increased by 14.1 percent when comparing the year ending December 2014 to the year ending December 2013," Auckland Airport General Manager Aeronautical Commercial Norris Carter said in a statement.

Subject to regulatory approvals, alliance services could commence as early as December 2015.

Air New Zealand stopped its twice-weekly direct flights between Beijing and Auckland three years ago. Endi