Most citizens of Iran, Libya, Syria, Yemen, Somalia, Chad, Venezuela and North Korea have been banned from travelling to the United States under a new executive order issued by President Donald Trump.

These nations are “currently inadequate in their identity-management protocols and information-sharing practices or present sufficient risk factors that travel restrictions are required,” according to the order, which also calls for tighter screening — but not a sweeping ban — on travel from Iraq.

“If you can’t screen people effectively to know who’s coming into your country, then you shouldn’t allow people from that country to travel,” said US National Security Advisor H.R. McMaster.

The decision was based on a previous executive order that outlined enhanced requirements for information-sharing with foreign countries, including rules on issuing electronic passports, sharing criminal data, reporting lost and stolen passports, and sharing personal passenger information.

Countries with residents wishing to visit the US also were required to help “identify serious criminals and known or suspected terrorists, as well as share identity-related information and exemplars of documents such as IDs and passports.”

The Trump administration said that the requirements were shared with other countries in July, which were given 50 days to come into compliance. Some made the required changes; these eight did not, according to the executive order.

Shortly after taking office, Trump announced a ban on travel from Iraq, Syria, Iran, Sudan, Libya, Somalia, and Yemen, sparking allegations that targeting these Muslim-majority nations amounted to religious-based discrimination. Sudan has since been dropped from that list.