Christians persecuted by Islamic State in the Middle East believe the world has forgotten them, but remain convinced that God is near, an Iraqi bishop has said.

Speaking to East County Magazine, Bishop Mar Shlemon Warduni, who has been working in San Diego but before that served in Baghdad, said: "our people are suffering too much".

"Nobody loves them, nobody takes care of them," he added. "The children, the young people, they have no future. They finish studying and they have no job. Always, we cry, all over the world, for those children."

Hundreds of thousands of Christians have fled the Middle East since the rise of ISIS, though some have remained behind. Both groups "sometimes... feel that nobody cares for us," the bishop said.

"Sometimes when we are in difficulties, we feel desperation, [but] we are all sons and daughters of hope... Our Lord tells us...'I am with you until the end of the war'."

He urged world leaders to do more to help those who have fled war and persecution in Iraq and Syria. "This is a very difficult issue," he said. "Presidents, ministries, they talk, but in reality what have the done? Those whom made it out of Iraq, they don't even give them exit visas; some have no food.

"For this I cry, I supplicate, I pray for everyone to do something. Where are human rights?"

Bishop Warduni will soon return to Iraq and, along with a number of church leaders in the region, has underlined the importance of Christianity being preserved in the Middle East.

Chaldean Archbishop of Erbil, Bashar Warda, last year said ISIS would not destroy the faith of his community.

"They've destroyed walls and historical sites, but they were unable to destroy the faith of the community," he said.

"And that's the good news, that our people are strong enough to leave everything behind and just stay Christians."