He said it is "unacceptable" that civilian victims of Syria's civil war are paying the price for the "the lack of desire for peace by the powerful".
Speaking on Sunday after the traditional Angelus prayer, he said that "it's unacceptable that so many helpless - including many children - must pay the price of the conflict, the price of closed hearts and the lack of desire for peace by the powerful".
He cited in particular the suffering around Aleppo, which is at the centre of a battle between the rebels and forces loyal to Syrian President Bashar Assad's government.
Rebels have claimed a breakthrough in breaking a government siege on rebel-held areas in the northern Syrian city, where the UN says 300,000 people are trapped.
Pope Francis has repeatedly spoken out about the war calling for peace but this is the first time he has said there is no desire for a ceasefire.