HANGZHOU, Sept. 4 (Xinhua) -- The Group of 20 (G20) summit under China's presidency opened Sunday amid multiple risks and challenges, aiming to prescribe a therapy that brings the sluggish world economy onto a healthy growth trajectory.

The summit will focus on a variety of topics essential to the world economy, including macro-economic policy coordination, innovation-driven growth, more efficient global economic and financial governance, robust trade and investment, inclusive and interconnected development, Chinese President Xi Jinping said when addressing the opening ceremony of the G20 summit.