WASHINGTON – President Donald Trump said Wednesday he plans to add yet-to-be-named countries to his divisive travel ban, an intensely contested policy that roiled his early days in the White House.

"We are adding a couple of countries to it," Trump told reporters at the end of an international economic conference in Davos, Switzerland. "Our country has to be safe."

Trump added that "it's going to be announced very shortly." The third anniversary of the president's initial announcement of the travel ban is Monday.

The current travel ban, which the administration re-worked during a series of court challenges, indefinitely suspends the issuance of immigrant and non-immigrant visas to applicants from Libya, Iran, Somalia, Syria, Yemen, North Korea and Venezuela.

Immigrant advocacy groups, noting that most of the affected countries are majority Muslim, said the current ban affects about 135 million people.

Trump did not specify Wednesday which countries he's considering adding to the list. But as the administration now considers changes, the list could be expanded to include countries dropped from previous versions of the ban, including Iraq, Sudan and Chad, administration officials said.

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The initial travel ban triggered a 17-month political and legal battle in which critics accused Trump of unconstitutionally targeting Muslims. The initial uproar included protests in cities and chaos at airports where some passengers from affected countries were detained.

After several changes by the administration, the Supreme Court upheld the ban on a 5-4 vote in 2018.

By returning to the ban, which Trump had promised during his 2016 campaign, he is once again moving legal immigration to the fore in an election year. The announcement comes as the Senate holds an impeachment trial of Trump on charges he abused the power of his office and obstructed Congress.

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It also comes on the heels of an international crisis with Iran in which that country launched more than a dozen missiles at Iraqi airbases housing U.S. soldiers earlier this month. Iranian officials said the strike was retaliation for Trump ordering the killing of Iranian Gen. Qasem Soleimani.

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Trump's first plan, in January of 2017, included a 90-day ban on travelers from Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen, and a 120-day ban on refugees worldwide.

After a series of lower courts struck down that plan, Trump came up with a second version. It dropped Iraq from the banned list, and exempted visa- and green-card-holders. Courts also struck down that version.

President Donald Trump

A third travel ban dropped Sudan, and added Chad, North Korea and government officials of Venezuela. That plan worked its way to the narrow Supreme Court approval rendered on June 26, 2018, though Chad was dropped from the list earlier that year and the case did not affect North Korea and Venezuela.

Secretary of State Mike Pompeo would not elaborate on what countries Trump plans to add to the travel ban list. During a news conference in Jamaica, where he visited with that country’s leaders, Pompeo said only: “Our policy is to make sure that we’re getting security right … Our obligation is to ensure that from where people are traveling to the United States, we protect America.”

Pompeo also said “we are constantly evaluating” security risks presented by travelers coming to the U.S.

Contributing: Deirdre Shesgreen

This article originally appeared on USA TODAY: President Donald Trump says he will add countries to his travel ban