Pope Leo, whose role in advocating for peace in Gaza has become notably stark since Israel struck the territory's only Catholic church last week, told Palestinian President Mahmoud Abbas on Monday that he opposed any forced displacement of Palestinians.

The Vatican said Abbas, who leads the internationally recognised Palestinian Authority, had phoned the pope on Monday, three days after Israel's Prime Minister Benjamin Netanyahu called and expressed regret over the strike on Gaza's Holy Family church.

Israel has said the strike, which killed three people and wounded the church's parish priest, was a mistake.

The small church in Gaza has been a focus of papal advocacy for peace throughout the war in the territory. Pope Leo's predecessor Pope Francis spoke to the parish nightly.

In Monday's conversation with Abbas, Leo condemned the "indiscriminate use of force" and any "forced mass displacement" of people in the Gaza Strip, the Vatican said.

Israel has said it wants Gazans to move to a special humanitarian zone in Gaza or leave the territory voluntarily. All mainstream Palestinian groups and neighbouring Arab states have rejected any plan that would displace them.

In emotional remarks on Sunday after his weekly Angelus prayer, Leo read out the names of those killed at the church in Gaza and called for an end to the "barbarity of war".