The Trump administration is banning immigration from Nigeria, Africa’s most populous nation, and three other countries in an expansion of its policy blocking travel from seven other nations.

WASHINGTON-POST is reporting that Citizens from Nigeria, Eritrea, Myanmar and Kyrgyzstan won’t be allowed to apply for visas to immigrate to the U.S. under the policy, which the Trump administration said was designed to tighten security for countries that don’t comply with the U.S. minimum security standards or cooperate to prevent illegal immigration.

Two other countries, Sudan and Tanzania, will be barred from participating in the diversity visa lottery, which randomly awards green cards to 50,000 immigrants from underrepresented countries annually. Many of the recipients are from African countries.

The six countries will join a list of seven nations, most of them Muslim-majority, that faced significant travel restrictions under President Trump’s original travel ban, issued in 2017.

That order was the administration’s third attempt to craft a legally workable policy fleshing out one of Mr. Trump’s top campaign promises, after the first two versions were met with significant criticism and struck down by federal courts.

However, unlike five of those original countries—Iran, Libya, Somalia, Syria and Yemen—travelers from the newly added nations who seek to visit the U.S. for business or pleasure will still be permitted entry.

None of the original restrictions, which also included bans against a small number of citizens from Venezuela and North Korea, are being lifted as part of Friday’s action.

Immigrant advocates denounced the coming restrictions ahead of their release, calling the new policy an “African Ban” and criticizing the administration for not imposing restrictions on other, larger nations that also don’t cooperate with the U.S.

“There are bad actors in Russia, bad actors in China, and none of those places have been put on any kind of ban,” said Rep. Sheila Jackson Lee (D., Texas.) whose Houston district includes the largest Nigerian community in the U.S. “It is pure discrimination and racism.”

Chad Wolf, acting Secretary of the Department of Homeland Security, said the new immigration restrictions were designed to address security concerns in the way the banned countries track their own citizens, share information with the U.S. and cooperate on immigration matters.

He outlined a process, which the department undertakes every six months under the president’s 2017 order, under which the U.S. government surveyed all other countries’ security practices.