The U.S. military successfully test-launched an intercontinental ballistic missile from California Wednesday, just days after North Korea's second test of an ICBM.
"The Secretary has authorized the restriction due to the serious and mounting risk of arrest and long-term detention of USA citizens under North Korea's system of law enforcement", the statement read.
Hundreds flee each year to China and make it to Thailand after an overland journey, from where they are usually sent on to South Korea.
"We don't think having a dialogue where the North Koreans come to the table assuming they're going to maintain their nuclear weapons is productive", he warned. Tillerson however expressed hope that Washington and Pyongyang can resolve their issues through negotiations.
US Defense Department spokesman Jeff Davis said was "irresponsible" of North Korea to conduct missile launches without giving prior notice.
Pentagon officials have said North Korea's missile launches are done with no coordination and are reckless.
The South Carolina senator said North Korea's continuing aggression toward the United States was forcing Trump to choose between homeland security and regional stability - a conflict in North Korea would place parts of China, Japan and South Korea in the crosshairs of a war, he said.
Trump's comments and the subsequent editorial come at a sensitive time in US, China relations. Experts suggest the US mainland is now within striking range. On Monday... President Trump promised to hold North Korea accountable.
Even talk about the possibility of a first military strike on North Korea is alarming some analysts. "We do not seek the collapse of the regime", Tillerson said.
"At the same time, we also call on all parties not to take any actions that will lead to an escalation in tensions". The U.S. also flew B-1B bombers along with South Korean and Japanese fighter jets over the Korean Peninsula on July 30, in response to North Korean tests.
Vandenberg Air Force Base announced an operational test launch of an unarmed Minuteman III intercontinental ballistic missile (ICBM) scheduled for August 2, after the Sun's August 1 press time.
"During these meetings, Secretary Tillerson will meet with his counterparts and discuss a range of issues including the denuclearization of the Korean Peninsula, maritime security, and counterterrorism", Nauert said.