King Abdullah II was addressing the United Nations General Assembly when he denounced all violence towards Christians.
He said: "The teachings of true Islam are clear: sectarian conflict and strife are utterly condemned.
"Islam prohibits violence against Christians and other communities that make up each country.
"Let me say once again: Arab Christians are an integral part of my region's past, present and future."
He was speaking as leaders discussed the threat to the world from Islamic State militants.
He added: "Those who say, 'this is not our business', are wrong.
"The security of every nation will be shaped by the fate of the Middle East.
"Together, we can and must undertake urgent humanitarian and security measures, create durable solutions for today's crises and provide new opportunities for dialogue, reconciliation, prosperity and peace."
King Abdullah II is known for his commitment to interreligious dialogue and has spoken out in support of persecuted Christians in the past.