Concerned by all acts of violence in Gaza; we urge all parties to honour their commitment: UN

United Nations: The United Nations was "concerned by all acts of violence in Gaza," spokesperson Stephane Dujarric said Monday, after a series of deadly weekend attacks threatened to wreck the fragile ceasefire between Israel and Hamas.

"We urge all parties to honour all of their commitments to ensure the protection of civilians and avoid any actions that could lead to a renewal of hostilities and undermine humanitarian operations," the UN secretary-general's spokesman said.

Gaza's civil defence agency, which operates under Hamas authority, said Israeli strikes killed at least 45 people across the territory on Sunday alone.

Four hospitals in Gaza confirmed the death toll to AFP, while Israel's military said it was looking into the reports of casualties.

Media restrictions in Gaza and difficulties in accessing many areas mean AFP is unable to independently verify the tolls provided by the civil defence agency or the Israeli military.

The army said that, after carrying out air strikes in response to a deadly attack on its soldiers, it had "renewed enforcement of the ceasefire" late Sunday but would "respond firmly to any violation of it".

Hamas denied knowledge of any attack, with one official accusing Israel of fabricating "pretexts" to resume the war.

A Hamas delegation was in Cairo on Monday for talks with Qatari and Egyptian mediators on the continuation of the truce, according to a source close to the negotiations.