At the end of his weekly audience at the Vatican, the 86-year-old pontiff called for prayers for peace, saying of both groups: "They suffer so much and I heard how they both suffer."

"Wars do this, but here we have gone beyond wars. This is not war, this is terrorism," he added.

The Vatican said last week the pope hoped to show his "spiritual closeness" during the private meetings, which it said would be "exclusively humanitarian in nature".

Each delegation told press conferences in Rome following the meetings that they believed Francis could use his moral influence to help them.

Israel has launched a major bombing campaign and ground offensive in Gaza, killing at least 14,100 people, more than two third of them are women and children.

"Let us pray that the difficulties resolve themselves in dialogue and negotiation and not with a mountain of dead on each side," Francis said in a video message released Wednesday.

Israel and the Palestinian resistance movement Hamas announced a deal on Wednesday allowing at least 50 captives and scores of Palestinian prisoners to be freed, while offering besieged Gaza residents a four-day truce after 48 days of all-out war.

The Palestinians present said the pope used the word "genocide" during their meeting to describe what was happening in Gaza.

​"He spoke to us about what he already knew about Gaza, and he's the one who described what's happened as a genocide", Shireen Hilal from Bethlehem insisted.

"I am not aware of him using that word," Vatican spokesman Matteo Bruni told AFP, adding that he had been present at the meeting.

The pope "used the terms he used to express himself during the weekly audience and words that in any case represent the terrible situation in Gaza", Bruni said.