FILE - Passengers wait to board their plane at Shanghai's Hongqiao International Airport.
FILE - Passengers wait to board their plane at Shanghai's Hongqiao International Airport.

STATE DEPARTMENT - The U.S. State Department has updated its travel advisory on China, calling on Americans to exercise "increased caution" in the country due to "arbitrary enforcement of local laws as well as special restrictions on dual U.S.-Chinese nationals."

The advisory says Chinese authorities have asserted broad authority to prohibit U.S. citizens from leaving China by implementing "exit bans," sometimes keeping U.S. citizens in China for years.  The warning says China uses exit bans "coercively" to compel U.S. citizens to participate in Chinese government investigations, to lure individuals back to China from abroad, and to aid authorities in resolving civil disputes in favor of Chinese parties.

Level 2 warning

The Level 2 warning says in most cases, U.S. citizens only become aware of the exit ban when they attempt to depart China.

It adds U.S. citizens under exit bans have been harassed and threatened.

China does not recognize dual nationality and the State Department warns U.S.-Chinese citizens and U.S. citizens of Chinese heritage may be subject to additional scrutiny and harassment, and China may prevent the U.S. embassy from providing consular services.

The travel advisory says extra measures, such as security checks and increased levels of police presence, are common in the Xinjiang Uighur and Tibet Autonomous Regions, where authorities may impose curfews and travel restrictions on short notice.

Advisory issued for Myanmar

The update calling for increased caution comes after China detained two Canadian citizens last month on suspicion of endangering state security.  Those arrests followed Canada's arrest of high-ranking Chinese executive Meng Wanzhou on Dec. 1 at the request of the United States.  China has demanded Canada free Meng, who is fighting extradition to the United States.

Last week, the State Department also issued a Level 2 advisory for Myanmar, calling on travelers to exercise increased caution "due to areas of civil unrest and armed conflict."  

Level 1 travel advisories call on American travelers to "exercise normal precautions."  Level 3 travel warnings call on Americans to reconsider travel, and Level 4 warnings strongly advise: "Do not travel."