China's President Xi Jinping and US President Donald Trump attend a welcome ceremony at the Great Hall of the People in Beijing

Donald Trump showered Chinese leader Xi Jinping with praise during talks in Beijing Thursday, but prodded his host to work fast to help resolve the North Korean nuclear crisis, warning "time is quickly running out".

Speaking on the second day of a trip to Beijing marked by pomp and pageantry, the US president also decried China's "one-sided and unfair" trade surplus with the United States but told Xi "I don't blame China", as the two countries signed more than $250 billion in business deals.

Xi hosted Trump at the imposing Great Hall of the People, next to Tiananmen Square, for the main event of the US president's five-nation tour of Asia.

While the two leaders exchanged pleasantries in keeping with their professed friendship -- with Trump calling Xi a "very special man" -- the former property magnate made clear that he expected China to do more to rein in North Korea.

"We must act fast. And hopefully China will act faster and more effectively on this problem than anyone," Trump said.

"China can fix this problem easily and quickly, and I am calling on China and your great president to hopefully work on it very hard," the US leader said.

"I know one thing about your president: If he works on it hard, it will happen. There's no doubt about it," he said, while thanking Xi for his efforts to restrict trade with Pyongyang.

The US administration thinks China's economic leverage over North Korea is the key to strong-arming Pyongyang into halting its nuclear weapons and missile programmes.

Xi said the two countries reiterated their "firm commitment" to the denuclearisation of the Korean peninsula and the implementation of UN resolutions.

He also repeated his plea for the issue to be resolved through negotiations, saying China was ready to discuss the "pathway leading to enduring peace and stability on the peninsula".

Though China has backed UN sanctions, US officials want Chinese authorities to clamp down on unauthorised trade along the North Korean border.

But China has resisted taking more drastic steps, such as halting crude oil exports to the North. Beijing fears that squeezing Pyongyang too hard could cause the regime to collapse.

US Secretary of State Rex Tillerson said there are signs that sanctions are "creating some stress within the North Korean economy" but that Xi told Trump they could take "a little while" to make a dent.

Trump, who may meet with Russian President Vladimir Putin at an Asia-Pacific summit in Vietnam on Friday, also urged Russia to "help rein in this potentially very tragic situation".

- Trade deals -

Washington has made no secret of its frustration at China's massive trade surplus with the United States, but at a signing ceremony for over $250 billion in US-Chinese business deals -- including $37 billion worth of planes from Boeing -- Trump said he did not blame Beijing.

"After all, who can blame a country for being able to take advantage of another country for the sake of its citizens?"

He blamed past US administrations "for allowing this out-of-control trade deficit to take place and to grow".

The Trump administration has aggressively pursued trade remedies in commercial relations with Beijing -- investigating Chinese trade practices on intellectual property and in aluminium and steel.

"There has been some friction on bilateral trade," Xi acknowledged, while pledging to open up China's economy "wider and wider".

While US and Chinese officials played up the deals, several of them were nonbinding memorandums of understanding, which can take years to materialise or never become firm contracts.

Tillerson downplayed the outcome of the trade talks: "Quite frankly, in the grand scheme... the things that have been achieved so far are pretty small".

- 'Beautiful welcome' -

The trip comes as Trump faces the lowest approval ratings for a US president in seven decades, and with the one-year anniversary of his election Wednesday spoiled by big Democrat wins in state and mayoral votes.

Xi, by contrast, cemented his status as the most powerful Chinese leader in a generation at a Communist Party congress last month, when his name was inscribed into the constitution.

On Trump's first state visit to China, ceremonial cannon fire erupted and the two leaders reviewed a military honour guard just across from Tiananmen Square -- the site of the army's deadly crackdown on pro-democracy protesters in 1989.

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