Changi Airport has plans for its fifth terminal to double the current passenger capacity by 2020.

It currently supports 66 million people per year. With a fourth terminal opening this will increase to 85 million passengers annually. The final, fifth terminal will be operational in the mid-2020s bringing this total to 135 million.

Josephine Tao, minister of state for finance and transport, said: "The Changi 2036 team was clear right from the start that our work is not only about airport expansion. It is also about a well-loved Singapore icon and how we keep Changi flying high."

Runway three is currently used by the military and is planned for an extension from 2.75km to 4km. This will allow it to handle larger aircraft. Additional taxiways totalling near 40km will also be built to connect the runway with the airport.

Ms Teo also added that Changi aims to be an important international hub for passengers. She added the airport will offer improved connectivity and open business and job opportunities.

The concept plan for the terminal is expected to be finalised in the first half of 2014, although consultancies and engineering studies are already underway.