The International Monetary Fund in April cut its forecast for global growth this year to 3.3%, warning that a sharp escalation in trade tensions could wreak havoc on supply chains and disrupt industries such as carmaking. That would be the weakest rate of expansion since the great recession of 2009.

"The global economy has hit a rough patch: investment has weakened and trade has slowed significantly, with export and import growth rates at their lowest level since the great financial crisis," IMF managing director Christine Lagarde said at the G20.

The big question now is how talks between the United States and China proceed.

Analysts at Berenberg, a German investment bank, said Monday that the US-China truce should be treated with caution. They noted that a meeting last year between Trump and Xi at the G20 summit in Brazil ended on a positive note, but talks later broke down leading both sides to impose new tariffs.

"Progress towards an eventual resolution that ends with both sides removing the tariffs enacted since Trump became US president and perhaps going further with a broad US-China trade deal remains far off," wrote Berenberg's Holger Schmieding and Kallum Pickering.

Trump's desire for a strong US economy and stock market heading into the 2020 presidential election could deter him from further escalating the trade war with China, or opening a new front with major trading partners such as Canada, Mexico or the European Union.

"A US economy that remains sufficiently strong is Trump's best bet for reelection," said the Berenberg analysts. "As US economy data has been softening of late, these recent positive steps on trade could be a sign that Trump is ready to ease up for a while to keep the economy on track."