(Bloomberg) -- The Trump administration said Friday it will add six new countries to its travel ban, part of an election-year crackdown that could reignite debate over whether the policy discriminates against Muslims.

Restrictions on entering the U.S. will now apply to certain travelers and migrants from Nigeria, Africa’s most populous country, as well as Sudan, Tanzania, Eritrea, Kyrgyzstan and Myanmar, according to a senior Department of Homeland Security official.

The updated policy would not ban all citizens of those countries from coming to the U.S., but instead would limit access to certain kinds of visas. Unlike the initial list, most of the countries just added do not have Muslim-majority populations.

President Donald Trump has demanded an end to a visa lottery program, calling people who use it the “worst of the worst.” He’s proposed overhauling immigration laws to allow in more skilled workers.

Trump has repeatedly misrepresented how the lottery works. Before being eligible for a random drawing, applicants must undergo a background check and show they have, at the minimum, the equivalent of a high school education or experience in a job that requires at least two years of training.

The roll-out of expanded restrictions covering additional countries comes about three years after Trump signed the initial travel ban during his first week in office, setting off a legal and political firestorm.

Trump and his aides have defended the travel restrictions as necessary to prevent terrorist attacks in the U.S. by limiting the arrival of people from countries they say have poor vetting and record-keeping standards.

But congressional Democrats and immigrant-rights activists have said the policy is discriminatory against Muslims. Trump in December 2015, almost a year before his election, called for a “total and complete shutdown of Muslims entering the United States.” Critics argue the travel ban is an outgrowth of that declaration.

Trump’s initial 2017 executive order banned people traveling to the U.S. from seven majority-Muslim countries. It set off nationwide protests and widespread chaos at airports, and was withdrawn after a federal judge struck it down.

A second version issued two months later was also knocked down by a pair of federal judges who ruled it had religious bias. The Supreme Court upheld a third version in a June 2018 ruling, voting 5-4 that the president has broad authority to set immigration policy.

The additions to the list were made as part of a worldwide assessment Trump required his administration to undertake every six months under the executive order that implementing the earlier travel ban.

Restrictions already apply to people from Iran, Libya, Somalia, Syria and Yemen. North Koreans and certain Venezuelan officials are also blocked from entering the U.S.

Chad was initially on the list but was removed in April 2018 after the administration said officials there improved information-sharing and identity-management efforts.

To contact the reporters on this story: Jordan Fabian in Washington at jfabian6@bloomberg.net;Justin Sink in Washington at jsink1@bloomberg.net

To contact the editors responsible for this story: Alex Wayne at awayne3@bloomberg.net, Joshua Gallu, Justin Blum

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