Eight new countries have been placed on a restricted list
The US has issued an extended travel ban that restricts or bans travel from a number of countries.
The White House says travel limitations and restrictions will be placed on people from Chad, Iran, Libya, North Korea, Somalia, Syria, Venezuela and Yemen.
The new measures came into effect on September 24th.
However Sudan - which was on the original ban on Muslim-majority countries - has been taken off the list.
Sudan has been taken off the list.
In a statement, the White House says: "Despite best efforts of the United States, several countries remain currently inadequate in their identity-management protocols and information-sharing practices or present sufficient risk factors that travel restrictions are required."
"These travel limitations and restrictions are a vital tool for enforcing adequate information sharing requirements and necessary for the security and welfare of the United States.
These limitations and restrictions are conditional, and these countries can, under this executive action, improve their information-sharing practices and receive relief from the limitations and restrictions."
US President Donald Trump has said that while Iraq should be subject to "great screening security", entry restrictions are not warranted.
The Trump Administration says it shared these new requirements with foreign governments in July, and countries "that did not have adequate information-sharing practices in place" were given 50 days to make necessary improvements.
"A number of nations that were not in compliance worked quickly and diligently to improve, such as increasing their information sharing with the United States or improving their reporting of lost and stolen passports.
"Many of those countries are now in compliance", the White House says.
Mr Trump has tweeted to say making America safe is his "number one priority", while including a link to the new travel restrictions.
Making America Safe is my number one priority. We will not admit those into our country we cannot safely vet.https://t.co/KJ886okyfC— Donald J. Trump (@realDonaldTrump) September 24, 2017