BEIJING, Sept. 15 (Xinhua) -- Premier Li Keqiang on Tuesday sent a congratulatory letter to the Second Global Grand Challenges Summit, calling for answers to global issues.

Li said that as the world was now facing resource shortages, pollution, climate change, disasters, epidemics and other challenges, multiple sectors across the international community must address those issues.

As the biggest developing country in the world, China is facing both developmental opportunities and a lot of challenges. Innovation and development can be used to address some of the challenges, Li added.

Li hoped that industrial, academia and engineering circles from across the world can improve cooperation and come up with feasible solutions to the challenges that the world is facing.

Jointly sponsored by the Chinese Academy of Engineering, the U.S. National Academy of Engineering, and the Royal Academy of Engineering, the two-day Second Global Grand Challenges Summit opened on Tuesday. Over 800 delegates from academic and industrial circles of the world joined the summit.