US President Donald Trump said he has asked the Department of War to prepare for possible "fast" military action in Nigeria if it fails to crack down on the killing of Christians.
The US government will also immediately stop all aid and assistance to Nigeria, Africa's most populous nation and top oil producer, Mr Trump said in a post on Truth Social.
If the United States sends in military forces, it would go in "'guns-a-blazing,' to completely wipe out the Islamic Terrorists who are committing these horrible atrocities," Mr Trump wrote, without providing any evidence of specifics about the treatment of Christians in Nigeria.
He called Nigeria a "disgraced country" and warned its government must move quickly.
"If we attack, it will be fast, vicious, and sweet, just like the terrorist thugs attack our CHERISHED Christians!" he wrote.
A spokesperson for the Nigerian presidency said Nigeria would welcome US assistance in fighting Islamist insurgents as long as its territorial integrity is respected.
The Department of War was formerly known as the Defense Department.
Secretary of War Pete Hegseth said on social media that his department is "preparing for action".
"The Department of War is preparing for action," he wrote on X. "Either the Nigerian Government protects Christians, or we will kill the Islamic Terrorists who are committing these horrible atrocities."
Yes sir.
— Pete Hegseth (@PeteHegseth) November 1, 2025
The killing of innocent Christians in Nigeria — and anywhere — must end immediately. The Department of War is preparing for action. Either the Nigerian Government protects Christians, or we will kill the Islamic Terrorists who are committing these horrible atrocities. pic.twitter.com/C0v9RHGoS1
Mr Trump's post on Nigeria came a day after his administration added Nigeria back to a "Countries of Particular Concern" list of nations that the US says have violated religious freedom. Other nations on the list include China, Myanmar, North Korea, Russia and Pakistan.
Before Mr Trump posted his attack threat, Nigerian President Bola Ahmed Tinubu earlier pushed back against claims of religious intolerance and defended his country's efforts to protect religious freedom.
"The characterisation of Nigeria as religiously intolerant does not reflect our national reality, nor does it take into consideration the consistent and sincere efforts of the government to safeguard freedom of religion and beliefs for all Nigerians," Mr Tinubu said in a statement, citing "constitutional guarantees to protect citizens of all faiths."
Nigeria's Foreign Ministry, in a separate statement, vowed to keep fighting violent extremism and said it hoped the US would remain a close ally, saying it "will continue to defend all citizens, irrespective of race, creed, or religion. Like America, Nigeria has no option but to celebrate the diversity that is our greatest strength."
The US military footprint in West Africa was significantly diminished when about 1,000 troops withdrew from Niger last year. While the US sometimes has small groups of troops in the region to take part in drills, the largest US military base on the continent is in East Africa in Djibouti, which hosts over 5,000 troops and is used for operations in the region.
Mr Trump had designated Nigeria a country of concern during his first term in the White House. His Democratic successor Joe Biden removed it from the US State Department list in 2021.
On Friday, Mr Trump said "thousands of Christians" were being killed in Nigeria by radical Islamists, but offered no details.
Nigeria, which has 200 ethnic groups practicing Christianity, Islam and traditional religions, has a long history of peaceful coexistence, but it has also seen flare-ups of violence among groups, often exacerbated by ethnic divisions or conflict over scarce resources.
The extremist Islamist armed group Boko Haram has also terrorised northeast Nigeria, an insurgency that has killed tens of thousands of people over the past 15 years. Human rights experts have said most Boko Haram victims have been Muslims.
US politicians such as Representative Tom Cole, a Republican who chairs the US House of Representatives Appropriations Committee, hailed Mr Trump's move, citing what they called "the alarming and ongoing persecution of Christians across the country."
The committee's fiscal 2026 national security appropriations bill included increased funding for international religious freedom programs and support for programmes supporting communities in Nigeria targeted by extremist violence.
Mr Trump's re-designation of Nigeria as a country of concern opens the door to a range of policy responses such as sanctions or waivers, but they are not automatic.
Some religious groups pressed Mr Trump for the re-designation in a letter last month, according to a copy on the Hudson Institute think tank's website.
"Christianity is facing an existential threat in Nigeria. Thousands of Christians are being killed. Radical Islamists are responsible for this mass slaughter," Mr Trump wrote without offering any specifics. He also called on the US House of Representatives Appropriations Committee to investigate.
