President Donald Trump has expanded a US travel ban, barring nationals of five additional countries and people travelling on Palestinian Authority-issued documents from entering the US.

The White House said the restrictions were intended to "protect the security of the United States" and will take effect on 1 January.

Full-entry restrictions will be imposed on people from Burkina Faso, Mali, Niger, South Sudan and Syria as well as Palestinian Authority passport holders.

The administration also moved Laos and Sierra Leone, which were previously subject to partial restrictions, to the full ban list and put partial restrictions on 15 other countries, including Nigeria, Tanzania and Zimbabwe.

Trump, who has tightened immigration controls since returning to the White House in January, said the expanded travel ban was necessary because of what his administration described as failures in screening and vetting systems overseas.

Officials cited high visa overstay rates, unreliable civil records, corruption, terrorist activity and a lack of cooperation in accepting deported nationals.

The announcement followed the arrest of an Afghan national suspected of shooting two National Guard troops over the Thanksgiving weekend, an incident the White House pointed to in highlighting its security concerns.

This is the third time Trump has imposed a travel ban.

During his first term, he introduced a similar order in 2017, which sparked protests and legal challenges at home and abroad. The policy was later upheld by the US Supreme Court.

The White House said the restrictions would remain in place until affected countries show "credible improvements" in identity management, information-sharing and cooperation with US immigration authorities.

A number of exceptions apply and the ban will not affect lawful permanent residents, many existing visa holders, diplomats, or athletes travelling for major sporting events. Officials said case-by-case waivers would also be available where travel is deemed to be in the national interest.

Countries with full restrictions:

• Afghanistan
• Burkina Faso
• Burma
• Chad
• Equatorial Guinea
• Eritrea
• Haiti
• Iran
• Laos
• Libya
• Mali
• Niger
• Republic of the Congo
• Sierra Leone
• Somalia
• South Sudan
• Sudan
• Syria
• Yemen
• Individuals travelling on Palestinian Authority issued or endorsed travel documents are also subject to a full suspension of entry

Partial restrictions:

• Angola
• Antigua and Barbuda
• Benin
• Burundi
• Côte d'Ivoire
• Cuba
• Dominica
• Gabon
• The Gambia
• Malawi
• Mauritania
• Nigeria
• Senegal
• Tanzania
• Togo
• Tonga
• Venezuela
• Zambia
• Zimbabwe

Special case:

• Turkmenistan (restrictions remain for immigrants, but have been lifted for non-immigrant visas)