Hamas was reviewing a proposal for a six-week truce, a source told AFP, after mediators gathered in Paris, with international efforts towards a new pause in the devastating war gathering pace.

In Gaza, there was no let-up in fighting or aerial bombardment, with the current focus of combat in the main southern city of Khan Yunis.

Overnight, witnesses said several Israeli air strikes hit the city, while aid and health workers have for days reported heavy fighting, particularly around two hospitals.

According to the Palestinian health ministry , 119 people were killed in the latest night of strikes.

"There is a massacre taking place right now," said Leo Cans, head of mission for international NGO Doctors Without Borders for the Palestinian Territories.

Due to constraints on the delivery of humanitarian aid, the population is "starving to death", the World Health Organization's emergencies director Michael Ryan said Wednesday.

"The civilians of Gaza are not parties to this conflict and they should be protected, as should be their health facilities," he added.

In its latest update, the UN reported heavy bombardment across the Gaza Strip, particularly in Khan Yunis, while it said 184,000 Palestinians from the city were registered to receive humanitarian assistance after fleeing their homes.

 Three-stage plan 

As Qatari and Egyptian-led mediation efforts intensified, Hamas leader Ismail Haniyeh was due in Cairo on Thursday to discuss a truce proposal thrashed out in Paris last weekend with CIA chief William Burns.

A Hamas source told AFP the three-stage plan would start with an initial six-week halt to the fighting that would see more aid deliveries into the Gaza Strip.

Only "women, children and sick men over 60" held by Gaza fighters would be freed during that stage in exchange for Palestinian prisoners in Israel, the source said, requesting anonymity due to the sensitivity of the talks.

There would also be "negotiations around the withdrawal of Israeli forces", with possible additional phases involving more captive-prisoner exchanges, said the source, adding the territory's rebuilding was also among issues addressed by the deal.

Tens of billions of dollars, and seven decades, would be required to rebuild Gaza, which "currently is uninhabitable" as half its structures are damaged or destroyed, the UN Conference on Trade and Development said.

Aid access 

Israeli Prime Minister Benjamin Netanyahu has ruled out pulling forces from Gaza and repeatedly vowed to destroy Hamas.

Netanyahu has also opposed releasing "thousands" of Palestinian prisoners as part of any deal, though his office on Sunday called the ongoing negotiations "constructive".

With the families of scores of Israeli captives still held in Gaza, there has been mounting criticism of Netanyahu's government -- sparking protests and even calls for early elections.

For people in Gaza, access to humanitarian aid has been further hampered by a major controversy surrounding the UN's agency for Palestinian refugees, UNRWA, after Israel accused several of its staff of involvement in the Hamas operation.

The claims last week saw several donor countries, led by key Israel ally the United States, freeze funding for the agency.

United Nations Secretary-General Antonio Guterres told a UN committee he had "met with donors to listen to their concerns and to outline the steps we are taking".

UNRWA spokeswoman Tamara Alrifai told AFP the agency supports "an independent investigation" into the Israeli claims that led to the funding crisis