In addition, North Korea has resisted even exchanging liaison offices, a step toward eventual diplomatic relations.
The commissioners of the New York City Police and Fire Departments said yesterday that for the first time they would exchange liaison officers and carry out specialized training together.
Once they reach a broad deal, analysts said, Mr. Kim could move to dismantle production facilities for intercontinental ballistic missiles and allow access to nuclear sites in the North; the two leaders could exchange liaison offices in Pyongyang and Washington; and Mr. Trump could ease sanctions, especially those that affect ordinary North Koreans.
"If that doesn't happen, it would be hard not only for Congress, but the Administration to proceed with other discussions, like exchanging liaison offices". American officials said they told North Korea that the wisest course would be to follow what South Korea did last January after capturing two North Korean soldiers who drifted into South Korean waters.
But that was much less specific than the 1994 pledge to exchange diplomatic liaison offices, and the 2005 pledge to work for a peace treaty to end the Korean War.
French Canadian students attended universities in France, teachers were exchanged, and some liaison developed between the press of the two countries, all of which were encouraged by Canada's Department of External Affairs.
Serbia and its former southern province exchanged official representatives, known as liaison officers, on Monday under a push by the European Union to improve ties between the Balkan neighbors five years after Kosovo declared independence.
Instead, American negotiators have been studying noneconomic incentives for the North, such as an end-of-war declaration or the exchange of liaison offices between Pyongyang and Washington, according to South Korean officials familiar with Washington's talks with North Korean officials.
The two countries have exchanged diplomatic properties and the U.S. has opened a Liaison Office in Hanoi.
