US President Donald Trump’s administration is considering significantly expanding its travel restrictions by potentially banning citizens of 36 additional countries from entry, according to an internal State Department cable.

Earlier this month, Trump signed a proclamation that banned the entry of citizens from 12 countries, saying the move was needed to protect the US against “foreign terrorists” and other security threats.

The directive was part of an immigration crackdown Trump launched this year at the start of his second term. It has included the deportation to El Salvador of hundreds of Venezuelans claimed to be gang members, as well as efforts to deny enrolments of some foreign students from US universities and deport others.

In an internal diplomatic cable signed by US Secretary of State Marco Rubio, the State Department outlined a dozen concerns about the countries in question and sought corrective action.

“The department has identified 36 countries of concern that might be recommended for full or partial suspension of entry if they do not meet established benchmarks and requirements within 60 days,” the weekend cable said.

The cable was first reported by The Washington Post.

The countries under consideration are: Angola, Antigua and Barbuda, Benin, Bhutan, Burkina Faso, Cabo Verde, Cambodia, Cameroon, Cote D’Ivoire, Democratic Republic of Congo, Djibouti, Dominica, Ethiopia, Egypt, Gabon, The Gambia, Ghana, Kyrgyzstan, Liberia, Malawi, Mauritania, Niger, Nigeria, Saint Kitts and Nevis, Saint Lucia, Sao Tome and Principe, Senegal, South Sudan, Syria, Tanzania, Tonga, Tuvalu, Uganda, Vanuatu, Zambia and Zimbabwe.

Among the concerns the State Department raised was the lack of a competent or co-operative government by some of the countries mentioned to produce reliable identity documents, the cable said.

Another was “questionable security” of that country’s passport.

The cable said some nations were not cooperating when their citizens had been ordered to be removed from the US. In other cases, citizens were overstaying US visas.

Other reasons for concern were that citizens of a country were involved in acts of terrorism in the US, or antisemitic and anti-US activity.

The cable noted that not concerns related to every country listed.

“We are constantly re-evaluating policies to ensure the safety of Americans and that foreign nationals follow our laws,” a senior State Department official said, declining to comment on specific internal deliberations and communications.

“The Department of State is committed to protecting our nation and its citizens by upholding the highest standards of national security and public safety through our visa process,” the official said.

The move would be a significant expansion of the ban that came into effect earlier this month.

The countries previously affected were Afghanistan, Myanmar, Chad, Congo Republic, Equatorial Guinea, Eritrea, Haiti, Iran, Libya, Somalia, Sudan and Yemen.

The entry of people from seven other countries – Burundi, Cuba, Laos, Sierra Leone, Togo, Turkmenistan and Venezuela – has also been partially restricted.