The measure, which Trump signed last week, restricts the nationals of Afghanistan, Myanmar, Chad, Congo-Brazzaville, Equatorial Guinea, Eritrea, Haiti, Iran, Libya, Somalia, Sudan, and Yemen from immigrating to the US.

Nationals from seven other countries - Burundi, Cuba, Laos, Sierra Leone, Togo, Turkmenistan, and Venezuela - will face stricter travel restrictions.

President Trump said new countries could be added to the list as "threats emerge around the world."