President Donald Trump signed a sweeping executive order on Wednesday that waives or suspends many federal travel restrictions on the ground that it’s too costly and that it will lead to more terrorism.

“As of today, the President has signed an Executive Order, which I call the Travel Ban, to eliminate any remaining travel restrictions and allow the entry of the United States to those nations for which it has a proven record of preventing, investigating, or prosecuting terrorism, as well as those nations that the President believes have an appropriate relationship with the United Kingdom, and those nations with which we have had successful cooperation and mutual trust,” Trump said in a statement.

While the executive order does not mention terrorism specifically, the order’s stated rationale is that it is necessary to protect the American people from “the threat of terrorism and its affiliates.”

The order allows the entry into the country of people who have a proven history of committing terrorism or have connections to such individuals.

The ban will be put into effect nationwide starting Friday and will be in effect for 90 days.

In addition to the ban on travel from certain countries, the executive orders also waives restrictions on citizens of the following countries: Burma, Cuba, Ethiopia, Iran, Iraq, Libya, North Korea, Somalia, Syria, Sudan, and Yemen.

The U.S. government has previously blocked entry to these countries, and they have a long history of ties to Islamic extremism and are generally viewed as dangerous by the U.K. and the U and European Union.

Other countries that are banned from entering the United State under the executive measures are Afghanistan, Bangladesh, Bolivia, Brazil, Cambodia, China, Central African Republic, Cuba (including the former Communist country), Democratic Republic of the Congo, Dominican Republic, El Salvador, Egypt, Eritrea, Ethiopia (including Eritrea), Guatemala, Honduras, Haiti, India, Israel, Jordan, Laos, Libya (including Libya) and Maldives (including Somalia).

As of Wednesday, the U,K., and the European Union have said they will allow citizens of these countries to visit the U of A and other U.k. universities.