Tensions run high between Washington and Pyongyang, with the communist nation aggressively pursuing its nuclear and missile programs.
The deal Iran signed with world powers to curb its nuclear program comes with an implicit promise that the Islamic Republic will be a "good neighbor".
"We (Americans) always treat North Korea like it's some kind of joke".
U.S. Secretary of State Rex Tillerson said Tuesday that the U.S.is willing to talk with North Korea - but only if North Korea gives up its pursuit of nuclear weapons.
Professional reporters or journalists, representatives of the International Committee of the Red Cross or the American Red Cross travelling on official missions, those travelling to North Korea for "compelling humanitarian considerations" and those whose requests are "in the national interest" may ask for a special validation of their passports in order to travel to the country, the State Department said.
"We are trying to convey to the North Koreans we are not your enemy, we are not your threat, but you are presenting an unacceptable threat to us, and we have to respond", he said.
The United States issued a ban on Wednesday prohibiting its citizens traveling to North Korea, a move triggered by the death of a U.S. student imprisoned by Pyongyang during a tourist visit.
He said other options were "not particularly attractive".
Identifying North Korea as one of the first threats encountered by the Trump administration, Tillerson said the threat has materialised in the ways they expected it would.
However, some North Korea watchers worry that inconsistent and opaque messaging from the United States has hamstrung their position when it comes to North Korea, a country which test-fired two long-range missiles in July that could theoretically reach the U.S. mainland.
North Korea has arrested and detained USA nationals in the past, sometimes using the detainees to leverage visits from high-level US officials.
A USA passport will only get you into North Korea for the rest of August, the State Department announced Wednesday.
In doing so, the Trump Administration has sought to partner with China, he added. "If we know about it, it's going to be sunk because opposition will grow to it", said Thayer.
"We do not see a regime change". "We continue to call upon them to use that influence with North Korea to create the conditions where we can have a productive dialogue".
Tillerson said the United States did not think of having a dialogue where the North Koreans come to the table assuming they are going to maintain their nuclear weapons is productive.