President Trump said on Sunday that there is a possibility of U.S. boots on the ground or airstrikes in Nigeria after he told the Department of Defense over the weekend to “prepare for possible action” in the country amid alleged attacks on Christians.

President Donald Trump said he has instructed the Pentagon to prepare for possible action in Nigeria, if the government "continues to allow the killing of Christians."

The move came a day after Trump designated Nigeria a "country of particular concern" over alleged violations of religious freedom.

The Nigerian government on Saturday vowed to keep fighting violent extremism and said it hoped Washington would remain a close ally after President Donald Trump added the West African nation to a U.S.

President Donald Trump escalated his criticism of Nigeria on Saturday, threatening to immediately halt all U.S. aid and assistance to the country while instructing the Pentagon to prepare for potential military intervention if the government fails to curb what he described as the "killing of Christians."

International Christian advocacy group Open Doors lists Nigeria as the seventh-most dangerous place for Christians on its World Watch list.

Christian persecution in Nigeria has ramped up dramatically as Islamist militants burn villages and kill thousands of believers in targeted attacks across the country.