Israel yesterday carried out air attacks on Gaza's northern city of Beit Lahiya, eastern areas of Gaza City and the southern city of Khan Younis, where artillery shelling has also been reported.

Palestinians have been hearing the sound of explosions over the past four weeks since the ceasefire was announced and was supposed to end all acts of violence on the ground.

The Israeli military has continued to demolish and detonate many remaining residential buildings.

UN Secretary-General Antonio Guterres on Wednesday described the ceasefire in Gaza as "fragile" and "repeatedly violated" while appealing for it to be respected and used to advance peace efforts.

"The ceasefire in Gaza is fragile, is repeatedly violated, but it is holding. And I strongly appeal for the ceasefire to be fully respected and to pave the way for the negotiations of phase two, leading to the creation of the conditions for the self-determination of the Palestinian people and the creation of the two-state solution," Guterres said at a news conference at UN headquarters in New York.

US Secretary of State Marco Rubio said Wednesday he was optimistic that the UN Security Council would finalize a resolution on Gaza that would back an international security force.

"We feel optimistic that it's going to happen," Rubio told reporters after G7 foreign ministers met in Canada.

Turkey's defence ministry said yesterday that main expectation from a planned International Stabilisation Force in Gaza is for it to provide guarantees that the fragile ceasefire will last.

Nato member Turkey has emerged as a critical player and mediator in ceasefire efforts, voicing a desire to join the stabilisation force despite Israel's repeated objections.

Meanwhile, Israeli forces yesterday rounded up at least 25 Palestinians in raids across the occupied West Bank, spanning the areas of Tulkarem, Hebron and Nablus, according to the Wafa news agency.

A group of Israeli settlers also set fire and inscribed racist slurs in a mosque near the West Bank town of Salfit.