More African countries could soon be caught in the cross-hairs of US president Donald Trump’s immigration clampdown.

Three years after issuing a controversial travel ban initially slapped on seven Muslim-majority countries, the Trump administration is planning to expand the ban to reportedly include four more African countries: Nigeria, Sudan, Tanzania and Eritrea. The others are: Belarus, Myanmar and Kyrgyzstan.

While not disclosing the countries set to be affected, Trump confirmed the plans on the sidelines of World Economic Forum in Davos. An announcement of the additional countries could be made as early as Monday, Politico reports.

Given the legal challenges the initial travel ban faced following which a watered-down version was implemented, additional countries are unlikely to face a blanket ban on all citizens. Instead, possible restrictions may include travel bans issued to government officials or issuing shorter-term visas on citizens. However, an inclusion on the travel ban list will likely result in increased scrutiny for visa applicants from those countries.

Some of the African countries that could be affected already have some history with the Trump administration.

Nigeria, the most high-profile country under consideration, has particularly come under focus from the White House. With Nigeria accounting for the third highest number of US visa overstays in 2018, the Trump administration has become tougher on Africa’s largest economy.

After indefinitely suspending its visa interview waiver for Nigerian applicants (the waiver allowed frequent travelers renew their visa without going through in-person interviews each time), the US also raised visa application fees for Nigerians by including additional “reciprocity fees” ranging from $80 to $303 depending on the class of visa. And even though the Nigerian government immediately slashed visa application fees for American applicants in a bid to get the US to reverse its price increase, the reciprocity fees remain in place. The clampdown measures have resulted in Nigeria recording the largest global drop-off in visitors to the US.

For its part, Sudan was one of the Muslim-majority countries initially named in the controversial Jan. 2017 travel ban. But, following legal challenges in US courts, Sudan was removed alongside Chad and Iraq. And, in Sept. 2017, Eritrea had all its nationals disallowed from applying tourist B visas for delays in accepting its citizens who had been ordered removed from the US.

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