Pope Francis prayed for the Syrian people affected by the violence in the war-torn country during his Sunday address.

Speaking to thousands of faithful gathered at St Peter's Square, he said he was concerned for the fate of Syrian refugees and called on the international community to find a political solution.

"I follow with deep concern the dramatic fate of the civilian populations involved in heavy fighting in our beloved Syria and forced to leave everything behind to escape the horrors of war," said the pontiff.

"I hope that with generous solidarity, help can be provided to assure their survival and dignity. I appeal to the international community not to spare any effort, to urgently bring the warring parties to the negotiating table. Only a political solution to the conflict will be able to guarantee a future of reconciliation and peace to that dear and martyred country. I ask you to pray much for it," he added.

He then led the crowd in reciting a Hail Mary for peace in Syria.

Since the civil war erupted in Syria five years ago, the conflict has killed an estimated 250,000 people and driven millions from their homes, with six million Syrians displaced within the country and more than four million others having left for Jordan, Lebanon, Turkey and beyond.