What we know about Trump's latest travel ban

Donald Trump has signed a ban on travel to the US from 12 countries, citing national security risks.

There are also seven additional countries whose nationals will face partial travel restrictions.

The US president said the list could be revised if "material improvements" were made, while other countries could be added as "threats emerge around the world".

It is the second time he has ordered a ban on travel from certain countries. He signed a similar order in 2017 during his first term in office.

Trump has signed a proclamation banning travel to the US from nationals of 12 countries:

Nationals from these countries will not be allowed to enter the US unless they qualify for an exemption.

There are an additional seven countries whose nationals face partial travel restrictions:

Those under the partial restrictions will not be able to travel to the US with certain visas.

The ban takes effect on Monday at 00:01 EDT (04:01 GMT), a cushion that avoids the chaos that unfolded at US airports when a similar measure took effect with virtually no notice eight years ago.

No end date has been provided. The order calls for periodic review.

The White House said these "common sense restrictions" would "protect Americans from dangerous foreign actors".

In a video posted to his Truth Social website, Trump said the recent alleged terror attack in Boulder, Colorado "underscored the extreme dangers" posed by foreign nationals who had not been "properly vetted".

Twelve people were injured in Colorado on Sunday when a man attacked a group gathering in support of Israeli hostages, throwing two incendiary devices and using a makeshift flamethrower.

The man accused of carrying out the attack has been identified as an Egyptian national, but Egypt is not included on the list of banned countries.

Trump has close ties with Egyptian President Abdel Fattah al-Sisi, who has in the past been described by the US president as his "favourite dictator".

Only two of the 19 countries are on the US government's State Sponsors of Terrorism list - Iran, which has a full ban, and Cuba, which faces partial travel restrictions.

But national security is given as a partial reason for the choices.

In the proclamation, Trump said many of the countries listed have a "historic failure to accept back their removable nationals" from the US, as well as having "taken advantage" of the US by exploiting its visa system.

He added that nationals from certain countries also "pose significant risks" of overstaying their visas.

There are a number of people from affected countries who may still be able to enter the US due to a number of exceptions. The order does not apply to:

In addition, the US Secretary of State may grant exemptions to individuals on a "case-by-case" basis, if "the individual would serve a United States national interest".

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