The U.S. Centers for Disease Control and Prevention on Monday raised its travel advisory for South Korea from Level Two to the highest Level Three after the number of confirmed coronavirus cases in the country topped 800.

The move came two days after the disease control agency issued a Level Two travel advisory for South Korea. 

By putting in place the Level Three warning, the agency urged Americans to avoid all nonessential travel to South Korea.

The only other country that the U.S. has issued the same level of advisory for with relation to COVID-19 is China. 

Meanwhile, a growing number of countries are banning non-residents travelling from South Korea. Hong Kong began such a ban from Tuesday, becoming the seventh country to do so after Israel, Bahrain, Jordan, Kiribati, Samoa and American Samoa.