Australian Prime Minister Scott Morrison. [Photo/Agencies]

Australian Prime Minister Scott Morrison has urged leaders of the world's 20 biggest economies to support third world countries amid the COVID-19 pandemic.

Morrison on Thursday night attended an extraordinary summit of the Group of 20 (G20) major economies by video-link to coordinate multilateral response to the pandemic.

The leaders pledged to work together and do whatever it takes to "minimize the economic and social damage from the pandemic", vowing to inject over 5 trillion U.S. dollars to boost the global economy.

Addressing the extraordinary meeting, Morrison appealed to fellow leaders to do whatever they can to prevent third world countries in southeast Asia, Africa and the Pacific from going bankrupt.

"By working together, we can amplify our national responses and assist those countries that need our support," he later told News Corp Australia on Thursday night.