TALKS aimed at securing a ceasefire in Gaza are stalling over the extent of Israeli forces' withdrawal from the Palestinian enclave, Palestinian and Israeli sources familiar with the negotiations in Doha said on Saturday.

The indirect talks over a US proposal for a 60-day ceasefire are nonetheless expected to continue, the sources said.

In Gaza, medics said 17 people trying to get food aid were killed on Saturday when Israeli troops opened fire — the latest mass shooting around a US-backed aid distribution system that the UN says has resulted in 800 people killed in six weeks.

Witnesses who spoke to Reuters described people being shot in the head and torso. Reuters saw several bodies of victims wrapped in white shrouds as family members wept at Nasser Hospital. The Israeli military said its troops had fired warning shots, but that its review of the incident had found no evidence of anyone hurt by its soldiers' fire.

Delegations from Israel and Hamas have been in Qatar for a week in a renewed push for an agreement which envisages a phased release of hostages, Israeli troop withdrawals, and discussions on ending the war.

US President Donald Trump, who hosted Israeli Prime Minister Benjamin Netanyahu over the past week, had said he hoped for a deal soon. But the Israeli and Palestinian sources described longstanding issues that remain unresolved.

A Palestinian source said that Hamas had rejected withdrawal maps which Israel had proposed that would leave around 40 per cent of Gaza under Israeli control, including all of the southern area of Rafah and further territories in northern and eastern Gaza.

Two Israeli sources said Hamas wanted Israel to retreat to lines it held in a previous ceasefire before it renewed its offensive in March.

The Palestinian source said matters regarding aid and guarantees on an end to the war were also presenting a challenge. The crisis could be resolved with more US intervention, the source said.

Hamas has long demanded an agreement to end the war before it would free remaining hostages; Israel has insisted it would end the fighting only when all hostages are released and Hamas is dismantled as a fighting force and administration in Gaza.