US President Donald Trump held out the possibility on Sunday of using trade as a lever to secure Chinese cooperation against North Korea and suggested Washington might deal with Pyongyang's nuclear and missile programmes on its own if need be.
The comments, in an interview published on Sunday in the Financial Times, appeared designed to pressure Chinese President Xi Jinping in the run-up to his visit to Trump's Mar-a-Lago resort in Florida this week.
"China has great influence over North Korea. And China will either decide to help us with North Korea, or they won't. And if they do that will be very good for China, and if they don't it won't be good for anyone," Trump was quoted as saying, according to an edited transcript published by the newspaper.
Asked what incentive the US had to offer China, Trump replied: "Trade is the incentive. It is all about trade."
Asked if he would consider a "grand bargain" in which China pressured Pyongyang in return for a guarantee that the US would later remove troops from the Korean peninsula, the newspaper quoted Trump as saying: "Well, if China is not going to solve North Korea, we will. That is all I am telling you."
It is not clear whether Trump's comments will move China, which has taken steps to increase economic pressure on Pyongyang but has long been unwilling to do anything that may destabilise the North and send millions of refugees across their border.
It is also unclear what the US might do on its own to deflect North Korea from the expansion of its nuclear capabilities and from the development of missiles with ever-longer ranges and the capacity to deliver atomic warheads.
Trump's national security aides have completed a review of US options to try to curb North Korea's nuclear and missile programmes that includes economic and military measures but leans more towards sanctions and increased pressure on Beijing to rein in its reclusive neighbour, a US official said.
Although the option of pre-emptive military strikes on North Korea is not off the table, the review prioritises less-risky steps and "de-emphasises direct military action", the official added, saying it was not immediately known if the National Security Council recommendations had made their way to Trump.
The White House declined comment on the recommendations.
Robert Kelly, an associate Professor of Political Science at Pusan National University, South Korea, told Al Jazeera that some people predict the US might in some way attack North Korea.
"Most people assume it could be some kind of an air strike. Ground options would certainly spark a major war, I don't think that is what the Trump people want. It is hard to see what naval action could happen, so I presume the Trump people mean air strikes, drones, bombings and things like that, but the North Koreans have been preparing for an American air strike for decades - the US bombed North Korea heavily during the war. Any air strike would not be pinpoint or surgical or short it would probably take several days, if not weeks.
"The North Korean military might feel compelled to respond. The North Korean military's prestige in the system and its access to the North Korean budget - which is very small - is all predicative in its ability to protect the state, so there will be a lot of pressure inside North Korea to do something if the campaign dragged on," Kelly said.
"I don't know how much Trump cares about what China thinks but if the Americans went over the heads of the Japanese and the South Koreans that would immediately end the alliance of the two of them, mostly because if the North Koreans did strike back they would not be able to hit the US; they would probably strike back on the American allies and that is Japan and South Korea, so we would need their approval to do it," he added.
Trump and Xi are also expected to discuss Chinese ambitions in the South China Sea, through which about $5 trillion in ship-borne trade passes every year, when they meet on Thursday and Friday. China claims most of the resource-rich South China Sea, while Brunei, Malaysia, the Philippines, Taiwan and Vietnam also have claims on the strategic waterway.
Secretary of State Rex Tillerson spoke on Sunday with China's top diplomat, State Councilor Yang Jiechi, about Xi's visit "and other issues of bilateral and regional importance", a State Department official said on condition of anonymity.
China's foreign ministry said in a statement on Monday about the call that Yang had described the meeting between Xi and Trump as being of "great significance" for peace, stability and prosperity in the Asia-Pacific region and the world at large.
Tillerson told Yang that the US would do its utmost to ensure that the meeting had "positive results", the ministry said.
Trump's deputy national security adviser, Kathleen Troia McFarland, said there was a "real possibility" North Korea could be capable of hitting the United States with a nuclear-armed missile by the end of Trump's four-year term, the Financial Times reported.
McFarland's estimate appeared more pessimistic than those of many experts.
"The typical estimates are that it will take five years or so," said Siegfried Hecker, a former director of the Los Alamos National Laboratory in the US and a leading expert on North Korea's nuclear programme.
Such estimates are notoriously hard to make both because of the scarcity of intelligence about North Korea and uncertainty about how high a success rate Pyongyang might want for such missiles.
John Schilling, a contributor to the "38 North" North Korea monitoring project, said Pyongyang might have missiles capable of limited strikes on the US mainland by the end of Trump's term, but "it will most likely be a bit later than that.
"I doubt that any missile they could put into service by the end of 2020 will be very reliable, but perhaps it doesn't have to be - one or two successes out of six launches against the US would be a political game-changer to say the least," Schilling said.
Source: Reuters news agency