In it, the defector offered a grim picture of life inside North Korea and the factors that motivated him to escape.
China's account of the bilateral meeting in Papua New Guinea made no mention of Mr Xi planning to go to North Korea.
"The United States is grateful for the sustained support of Sweden, our protecting power in North Korea, for its advocacy on behalf of American citizens".
"Relevant authorities have made a decision to expel him from the country".
Last year, U.S. media said the man expelled from South Korea - who has also been named as Lawrence Bruce Byron - had claimed he wanted to help resolve tensions between North Korea and the US.
Although heavily-sanctioned Pyongyang is easily outspent in defense funding by Seoul and Washington, the North's forward-deployed troops, guns and multiple-launch artillery rocket systems pose a significant threat to the allies.
The latest detained American is likely a man that South Korea deported a year ago, according to South Korean police.
Media reports said that Bryon told South Korean officials he sought to facilitate talks between North Korea and the United States, although he is a private citizen. Yang Wook, a Seoul-based military expert, said a "tactical weapon" in North Korea refers to "a weapon aimed at striking South Korea including US military bases" there, so the North may have tested a short-range missile or a multiple rocket launch system.More news: Trump wants 'rules and regulations' for reporters
Pyongyang has positioned a large assortment of conventional weapons within striking distance of the South Korea capital.
"It would be premature to ease sanctions at this point", said Troy Stangarone, senior director of the Korea Economic Institute. The testing of the highly developed weapon has occurred in a sensitive time period, with USA hopes for nuclear disarmament and Pyongyang's recent release an American prisoner. He may take action next week, next month or next year.
"The financial and more general trade restrictions should remain until Pyongyang moves toward permanent reduction and ultimate elimination of its nuclear weapons", Brown said.
The US State Department downplayed the news. That mysterious formulation seems to imply---absurdly-that North Korea had somehow welshed on an obligation to fully inform the United States of its missile assets in advance of a negotiated agreement on the sequence and timing of the steps both sides would need to take to conclude an denuclearization agreement.
Gause, of the International Affairs Group, said he believes Washington will ease sanctions only when it thinks sanctions are ineffective. North Korea can not give them up without losing completely its ability to deter outside attack, since it does not have a modern air force with the necessary capability for deterrence. "We can not confirm what it is", a defense ministry spokesman said.
Most young North Koreans feel no loyalty to Kim Jong-un and have little interest in their country's politics, according to a young soldier who was riddled with bullets by his own comrades as he fled over the border to South Korea.
"I think it will be absolutely imperative in this next summit that we come away with a plan for identifying all of the weapons in question, identifying all the development sites, allowing for inspections of the sites and the plan for dismantling nuclear weapons", Pence said.