The United States Department of State has updated its global travel advisory, placing 23 countries under its highest warning level and advising American citizens not to travel to those destinations.

According to the advisory, countries designated under Level 4: Do Not Travel are considered to pose severe security risks or have conditions that limit the U.S. government’s ability to provide assistance to its citizens.

The countries on the Level 4 advisory are:

Afghanistan

Belarus

Burkina Faso

Myanmar (Burma)

Central African Republic

Chad

Democratic Republic of the Congo

Haiti

Iran

Iraq

Lebanon

Libya

Mali

Niger

North Korea

Russia

Somalia

South Sudan

Sudan

Syria

Uganda

Ukraine

Yemen

The State Department said the Level 4 designation is reserved for destinations where security conditions are considered extremely dangerous, warning Americans not to travel to those countries for any reason.

Of the 23 countries, 11 are in Africa: Burkina Faso, Central African Republic, Chad, Democratic Republic of the Congo, Libya, Mali, Niger, Somalia, South Sudan, Sudan and Uganda.

Meanwhile, Nigeria remains under the Level 3: Reconsider Travel advisory due to concerns over crime, terrorism, kidnapping, civil unrest and inconsistent healthcare services.

However, the U.S. has maintained a Level 4 advisory for several Nigerian states because of heightened security risks. These include Borno, Jigawa, Kogi, Kwara, Niger, Plateau, Taraba, Yobe and northern Adamawa in the North, as well as Abia, Anambra, Bayelsa, Delta, Enugu, Imo and Rivers State, excluding Port Harcourt, in the South.

Reacting to the advisory, the Nigerian government described the U.S. decision as a routine precaution based on its internal protocols rather than a reflection of the country’s overall security situation.

Minister of Information Mohammed Idris acknowledged that Nigeria faces isolated security challenges but maintained that there has been no breakdown of law and order, adding that the country remains stable.