Trump's US travel ban: What's the full story?
The United States has extended a travel ban to include people from three more countries: North Korea, Venezuela and Chad.
The White House has already placed travel restrictions on some countries. The updates to the ban means these three countries join five others from the original ban list: Iran, Libya, Syria, Yemen and Somalia.
The new ban on Venezuela will only apply to some government officials and their family members. Restrictions placed on Sudan were removed.
The White House says it has expanded the ban because of how information is shared between the countries' governments.
"Making America safe is my number one priority. We will not admit those into our country we cannot safely vet," Mr Trump said.
The restrictions come into effect on 18 October. So what's the story behind the US travel ban?
Where did the travel ban come from?
On 27 January 2017, Donald Trump brought in a temporary travel ban which blocked people from seven countries from entering America.
It stopped nationals from Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen from being allowed to travel to America for 90 days. This included those who shared dual nationality with other countries, including the UK.
It also included a temporary ban on all refugees entering the US for 120 days. However, Syrian refugees were not to be allowed to travel to the country until further notice.
Syria is a country in the Middle East that has been greatly affected by violence and war. It has led to many ordinary people living there - including lots of children - needing to leave the country to try to find safety.
There was a lot of confusion about how the ban worked, but the UK government said only dual citizens travelling from one of the seven countries would be affected.
Mr Trump said the plans were about keeping America safe from terrorism and that it was not a ban against Muslims, but many people disagreed because the majority of people living in six of the countries on the list are Muslims.
He continued to support the ban, despite widespread protests against it.
Thousands gathered at airports around the US to protest against the ban, including lawyers who offered their services for free to help those affected. People also protested outside Mr Trump's home, the White House, in the capital Washington DC.
More than 1.5 million people also signed a UK petition calling to stop Mr Trump from making a state visit to the UK. A state visit is an important occasion which would include an invitation for Mr Trump to meet the Queen, so it is an honour to have one.
There was also another petition with more than 90,000 signatures saying that the state visit should be allowed to happen.
Why did he introduce a travel ban?
The US president made immigration a big issue in his election. The things he has said about migrants and refugees made him popular with his supporters.
Mr Trump said in January that his decision to introduce the ban was part of plans to keep radical terrorist groups out of the country.
In January, he tweeted that the US needed "extreme vetting, NOW". But later, in a statement, tried to offer more reassuring words, saying: "This is not about religion - this is about terror and keeping our country safe."
He sacked the US attorney general Sally Yates - an important job in law in America - after she questioned what he had done.
A spokesperson for UK Prime Minister Theresa May said she "did not agree" with the restrictions.
What has happened since it was introduced?
Since the ban was introduced, there have been legal challenges against it.
It was blocked by a judge, who said it could be "unconstitutional", which means it goes against the laws that the US is founded on.
But Donald Trump challenged this, saying that it does not break the law.
He has revised the ban since it was first introduced. Iraq was taken off the list after it agreed to conditions from the US government and the indefinite ban on Syrian refugees was lifted.
After legal challenges to the ban, In June 2017, the top court in America called the Supreme Court ruled that parts of Donald Trump's ban could go ahead.
So what now?
The ban is still due to be considered by the US Supreme Court in October, as it was only partly reinstated in July.
It is not clear how these new changes will affect what is happening in the courts, if at all.
One of the original criticisms of the ban was that the countries on it were majority-Muslim countries, so it was being called a "Muslim ban".
North Korea and Venezuela, which have just been added, are not majority-Muslim. We will have to wait to see what will happen in the coming months.