What to know for Trump travel ban: List of countries, who is impacted and more

President Donald Trump announced Wednesday night that nationals from 12 countries would be banned from entering the United States starting Monday

President Donald Trump announced Wednesday night that nationals from 12 countries would be banned from entering the United States starting Monday.

Trump said that the ban, which primarily targets countries in Africa and the Middle East, was necessary to preserve national security and prevent terrorism in the United States.

"As President, I must act to protect the national security and national interest of the United States and its people," Trump's proclamation reads. "I remain committed to engaging with those countries willing to cooperate to improve information-sharing and identity-management procedures, and to address both terrorism-related and public-safety risks."

Nationals of the following 12 countries will be blocked from entering the United States: Afghanistan, Chad, Equatorial Guinea, Eritrea, Haiti, Iran, Libya, Myanmar, the Republic of Congo, Somalia, Sudan and Yemen.

In addition, nationals of seven other countries will be barred from coming into the United States permanently or under several visa programs: Burundi, Cuba, Laos, Sierra Leone, Togo, Turkmenistan and Venezuela.