"May all parties abandon the attempt to resolve issues by the use of arms and return to negotiations," he said as he met Syrian refugees in Jordan on the first day of a lightening trip to the Middle East.
The pontiff said the three-year civil war would only be brought to an end "through dialogue and restraint... Through the search for a political solution."
The 77-year-old, famed for his ceaseless dedication to the world's downtrodden, called on the world to assist Jordan in giving safe haven to the refugees, around 6,00,000 of whom have sought shelter in the kingdom.
In an unscripted message at the end of his speech, Francis railed against those fuelling conflict in the region, saying he would "convert the violent, those who have designs for war, those who manufacture and sell weapons.
