Full coverage: G20 Hangzhou Summit

A G-20 trade ministers meeting comes against the backdrop of weak global trade and murky cross-border investment sentiment.

The WTO says global trade will grow 2.8 percent in 2016. That's the fifth year of growth lower than 3 percent. The momentum will pick up in 2017.

On investment, global FDIs will drop 10 percent to 15 percent in 2016. That's a shortfall from 2015. But the sector will pick up again in 2017 and continue to grow in 2018. Global FDIs are dragged by overall weak demand and shrinking profits of multinationals. Governments' anti-tax-evasion policies also reduce cross-border investments.

Bucking the trend, the WTO says China's outbound investment will hit a new high in 2016. The investments include M&A deals in advanced markets, and belt-and-road related industrial capacity cooperation efforts in developing countries.