The political backlash over global trade is the backdrop to the G20 Summit in Hangzhou, and Chinese President Xi Jinping began with a plea against protectionism.

Xi told the gathering of world leaders from the nation's 20 largest economies that their countries need to "enhance mutual understanding" in order to face a "crucial juncture for the world economy."

"The world today is undergoing profound changes never seen before," he said. "It's imperative we blaze a new trail to bring an innovative, invigorated, interconnected and inclusive world economy and a new round of robust growth."

He added that "growth drivers from the previous round of technological progress are gradually fading, while a new round of technological and industrial revolution has yet to gain momentum," according to Reuters, and Xi asked the G20 leaders to be an "action team, instead of a talk shop."

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Promoting orderly globalization is one of the founding purposes of the G20 summit. And most of the world leaders -- including President Obama -- are in favor of upholding trade deals and speak strongly on the importance of international cooperation.

Xi's speech is significant because China has been one of the largest beneficiaries of international trade deals, but protectionism and isolationism are on the rise in some countries where people view the deals as job killers.

And China frequently faces criticism that it manipulates global markets and makes life difficult for foreign companies operating on its turf. For example, the country has come under fire from the U.S. and Europe over the flood of steel and other raw materials it has unleashed on world markets.

"President Xi accurately raised the alarm on the need to counter the increase in protectionism around the world; but actions speak louder than words and the ball is in China's court to implement its own needed domestic reforms and to provide greater market access for foreign goods, services and technology," said James Zimmerman, chairman of the American Chamber of Commerce in China.

Republican presidential nominee Donald Trump opposes international trade deals like the Trans-Pacific Partnership -- a pact involving 12 countries across four continents. He called the TPP an "attack on America's business." Democratic nominee Hillary Clinton is proponent of trade, but she also opposes the TPP, saying it's cost American jobs.

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Then there's Britain's decision to exit the European Union, putting $1.3 trillion worth of global trade at stake.

Over the course of the two-day summit, finance ministers, central bank governors and other world leaders were meeting to discuss a wide range of economic topics.

-- Jethro Mullen contributed to this report.

Correction: An earlier version of this story misstated the number of countries involved in the Trans-Pacific Partnership.