Tens of billions of dollars of new investment is needed in LNG projects to avoid a supply crunch in the 2020s, Royal Dutch Shell has warned.

The global market is still absorbing supplies from a wave of LNG megaprojects built in Australia over recent years, as well as the emergence of the U.S. as a net gas exporter for the first time in more than half a century.

But Shell, one of the world’s largest suppliers of LNG, said renewed investment was needed to meet surging demand from China and other developing countries.