Super powers China and the USA have agreed to restart trade talks after a much-anticipated meeting between Donald Trump and Xi Jinping at the G20 Summit in Japan.

After weeks of global economic uncertainty sparked by the two countries’ escalating trade war, Mr Trump has offered concessions including no new tariffs and an easing of restrictions on tech company Huawei.

The world breathed a sigh of relief as China also agreed to make unspecified new purchases of US farm products and return to the negotiating table.

However no deadline was set for progress on a deal, and the world’s two largest economies remain at odds over significant parts of an agreement.

Financial markets, which have been rattled by the nearly year-long trade war, are likely to cheer the truce.

Washington and Beijing have slapped tariffs on billions of dollars of each other’s imports, threatening to put the brakes on an already slowing global economy. Those tariffs remain in place while negotiations resume.

“We’re right back on track,” Mr Trump told reporters after an 80-minute meeting with Chinese President Xi Jinping.

“We’re holding back on tariffs and they’re going to buy farm products.”

US President Donald Trump, Japan’s Prime Minister Shinzo Abe and China’s President Xi Jinping at a meeting on the digital economy at the G20 Summit in Osaka. Photo: Getty

The US president had threatened to slap new levies on roughly $US300 billion ($427 billion) of additional Chinese goods, including popular consumer products, if the meeting proved unsuccessful.

Such a move would have extended existing tariffs to almost all Chinese imports into the US.

In a lengthy statement on the two-way talks, China’s foreign ministry quoted Mr Xi as telling Mr Trump he hoped the US could treat Chinese companies fairly.

“China is sincere about continuing negotiations with the United States … but negotiations should be equal and show mutual respect,” the foreign ministry quoted Mr Xi as saying.

Mr Trump offered an olive branch on Huawei, the world’s biggest telecom network gear-maker.

The Trump administration has said the Chinese firm is too close to China’s government and poses a national security risk, and has lobbied US allies to keep Huawei out of next-generation 5G telecommunications infrastructure.

Huawei had been placed on the USA’s “entity list”, effectively banning the company from buying parts and components from US companies without US government approval.

But Mr Trump said on Saturday he did not think that was fair to US suppliers, who were upset by the move.

“We’re allowing that, because that wasn’t national security,” he said.

China welcomed the step.

“If the US does what it says, then of course, we welcome it,” said Wang Xiaolong, the Chinese foreign ministry’s envoy for G20 affairs.

Mr Trump has also tweeted a proposal for a weekend meeting with North Korea’s Kim Jong-un in the demilitarised zone between North and South Korea.

North Korea’s state news agency KCNA quoted Choe Son-hui, North Korea’s first vice-minister of foreign affairs, responding: “We see it as a very interesting suggestion, but we have not received an official proposal.”

“If the DPRK-US summit meetings take place on the division line, as is intended by President Trump, it would serve as another meaningful occasion in further deepening the personal relations between the two leaders and advancing the bilateral relations,” Mr Choe said in a statement.

After some very important meetings, including my meeting with President Xi of China, I will be leaving Japan for South Korea (with President Moon). While there, if Chairman Kim of North Korea sees this, I would meet him at the Border/DMZ just to shake his hand and say Hello(?)!

— Donald J. Trump (@realDonaldTrump) June 28, 2019

Meanwhile global tech giants such as Google, Facebook and Twitter have been put on notice about the way they handle content showing terrorism or violent crime.

Global leaders have signed an agreement to take on social media companies that fail to act on live streaming of violence or terrorism.

It comes in the wake of the Christchurch massacre which was livestreamed on Facebook as it unfolded.

Australian Prime Minister Scott Morrison earned a significant victory by convincing all leaders of the world’s major economies to agree to take action.

“We urge online platforms to step up the ambition and pace of their efforts to prevent terrorist and VECT (violent extremism conducive to terrorism) content from being streamed, uploaded, or re-uploaded,” the statement released on Saturday said.

“We issue this statement to raise the bar of expectation for online platforms to do their part.”

Mr Morrison said the consensus position from G20 leaders sent a clear message to technology companies.

“The impetus of this is to say to the companies, you have the technology, you have the innovation, you have the resources, and now you have the clear communicated will of the world’s leaders to get this right,” he told reporters in Osaka.

The Morrison government has already enacted laws to make it a criminal offence for companies not to take down videos that show abhorrent violent content, and these were held up to G20 leaders as the gold standard.

-with wires