Members of the lower chamber of parliament, the House of Representatives, voted Wednesday to summon Buhari over the clashes that have claimed nearly 400 lives since January.
House speaker Yakubu Dogara said late Wednesday that lawmakers “passed a vote of no confidence on service chiefs and security advisers and called for their replacement”.
“We also resolved to summon (Buhari) in order to answer pertinent questions concerning what the Executive is doing to put a decisive end to the spate of killings in different states of the Federation,” he wrote in a tweet.
“The foremost responsibility of government is to ensure the safety of lives and property and as a responsive Legislature backed by the mandate of our constituents, we cannot continue to look on as our people are murdered in cold blood.”
Much of the violence has been in Benue state, where some 385 people have been killed in clashes since January, according to the US-based Armed Conflict Location and Event Data project.
On Tuesday, at least 18 people, including two Catholic priests, were killed in an attack on a church near the state capital Makurdi that was blamed on herdsmen.
Eleven ethnic Hausa traders were killed in Makurdi in retaliation.
Thousands of people have been killed over decades in clashes between cattle herders and farmers over land and water, with the conflict polarised along religious and ethnic lines.
Critics of Buhari say he has done little or nothing to stop the violence because the herders are his kinsmen from the mainly Muslim north of the West African country.
Buhari, elected in 2015, has promised to be tough on “insurgency, terrorism, ethnic and religious violence, kidnapping (and) rural banditry”.
He is seeking re-election in February next year.