US President Donald Trump on Monday praised China for its role in the denuclearization of the Korean Peninsula but also blamed the country and several others for what he called unfair trade deals.

Speaking to a group of US governors at the White House, Trump said he has great respect for President Xi Jinping.

"I think that President Xi is unique. He's helping us with North Korea - who, by the way, wants to talk, as of last night; you heard that," Trump said.

Kim Yong-chol, who headed the Democratic People's Republic of Korea's delegation at the closing ceremony of the 2018 Winter Olympics in South Korea, said on Monday that his country is willing to hold talks with the US, noting the door for dialogue between the two countries remains open, South Korea's Yonhap News Agency quoted an official from Seoul's presidential office as saying.

Kim's remarks came just a day after he told South Korean President Moon Jae-in that the DPRK has "enough willingness" to hold bilateral talks with the US.

"They want to talk. And we want to talk also, only under the right conditions. Otherwise, we're not talking," Trump told the US governors.

The US president blamed his predecessors Barack Obama, George W. Bush and Bill Clinton for not being effective in addressing the issue.

Trump announced stricter sanctions on the DPRK last Friday, eliciting condemnation from North Korea, which called the US measures "an act of war".

"China has been good, but they haven't been great," said Trump of China's role in the issue. "China has really done more, probably, than they've ever done because of my relationship. We have a very good relationship, but President Xi is for China, and I'm for the United States."

Trump criticized Russia for "behaving badly" on the issue but added that he believes Russia wants to see the issue come to an end, too.

"First time - they want to talk. And we'll see what happens," Trump said of the DPRK.

In Beijing, Foreign Ministry spokesman Lu Kang welcomed the message from the meetings of the two Koreas.

He said China has stressed many times that the core of the Korean Peninsula nuclear issue is about security, the settlement of which hinges on the DPRK and the US.

"Thus, direct talks between the two parties are indispensable if the Korean Peninsula nuclear issue is to be resolved and a fundamental turnaround in the Korean Peninsula situation is to be achieved," Lu told a press briefing in Beijing on Monday.

China has long called for a dual-suspension approach to ease tension on the peninsula, to pave the way for denuclearization. That is for the DPRK to halt its nuclear and missile tests, and the US and South Korea to cease their joint military drills.

In front of US governors, Trump also said that China, Mexico, Canada and India take advantage of the US in trade. But he said when he gets too tough with a country, US lawmakers always call to say, "Oh, gee, don't do that."

Canada, Mexico and China are three of the largest trade partners for most US states, and a trade war or major tit-for-tat retaliation is expected to hurt both the local economy and jobs.

"Because of China, we probably lost $504 billion, last year, on trade - $504 billion," Trump said.

The figure turned out to be misleading.

A US Commerce Department report shows that in 2017, US imports from China were $505 billion and US exports to China were $130 billion, a surplus of $375 billion in China's favor.

Many economists have argued that the bilateral trade deficit does not matter, and the US trade deficit has more to do with the country's fiscal policy, low savings rate and the role of the dollar as a global reserve currency.

The US has been running a consistent trade deficit since 1976, and it had a trade deficit with 99 economies in 2016.