The tireless work of churches and aid agencies in the Middle East is "a reflection of God's mercy" and a sign that "evil has limits", Pope Francis has said.

Speaking to representatives from more than 40 Catholic aid agencies and churches, the Pope warned that the cycle of violence in places like Iraq and Syria can seem unbreakable.

"Violence begets violence, and we have the impression of being caught up in a spiral of arrogance and inertia from which there is no escape," Francis said during his address.

"The work of all who like you, represent so many workers in the field, who are committed to helping refugees and to safeguarding their dignity, is certainly a reflection of God's mercy and, as such, a sign that evil has limits and does not have the last word."

Director of humanitarian and emergency response at CAFOD, Matthew Carter, said following the meeting on Friday that "Ensuring that humanitarian access remains our number one priority in order to provide emergency assistance to men, women and children.

"The suffering is some of the worst I have witnessed and must be averted and people kept alive," he continued.

"Vulnerable people must be given access to water, food and urgent medical assistance and this is their right under international humanitarian law. Long term peace in the region is essential but the priority must be to end the conflict immediately, to stop the violence, killing and atrocities."

This was reflected in Pope Francis' speech, Carter added.

"The Pope's message is loud and clear we cannot be paralysed by the enormity of this conflict, instead we must continue to do all that we can to reach those in need both inside of Syria and in neighbouring countries."