The meeting's great success is $1.1 trillion in economic aid for the developing world, but other proposed solutions to the recession were vague.
At the G-20 summit, the US, Japan, and South Korea are attempting to win backing for a Security Council resolution against North Korea.
The global crisis has led to political upheaval in many countries, unseating three prime ministers in Europe alone.
Pyongyang had previously warned others not to shoot down a rocket it says it will launch between April 4 and April 8.
The US has said it won't use destroyers to shoot missiles down. But they could gather intelligence.
South Korean fighter pilots are 'ready to scramble' as North Korea prepares a missile launch.