'Heartbroken' PM says Israel breached international law

The prime minister spoke of his emotional response to images of gaunt and dying children in the Palestinian territory, while acknowledging increased airdrops of aid by Israel was "a start".

"It just breaks your heart," he told ABC's Insiders on Sunday. 

"A one-year-old boy is not a Hamas fighter, and the civilian casualties and deaths in Gaza is completely unacceptable. It's completely indefensible.

"Quite clearly it is a breach of international law to stop food being delivered, which was a decision that Israel made in March. It's a breach of decent humanity and of morality, and everyone can see that."

Australian National University Professor Donald Rothwell, a leading expert in international law, said he could not think of a previous example of an Australian prime minister making such a direct and clear statement concerning Israel.

"It's rather exceptional that an Australian prime minister would make such a clear comment about a breach of international law by another state," he told AAP.

He said while unprecedented, Mr Albanese's claim did not appear to be without merit.

"I'm always very cautious to comment about this, but all I can say is that the evidence that I see on my television screen is fairly compelling," Prof Rothwell said.

Not only were Gazans suffering from a lack of food, but dangerous conditions around aid points had resulted in desperate civilians being shot and killed as they sought support, Medecins Sans Frontieres Australia executive director Jennifer Tierney said.

"We are seeing one in four people in our clinics who are malnourished," she told ABC News. 

Ms Tierney urged Australians horrified by the scenes in Gaza to get in touch with their MPs and let their feelings be heard.

Thousands of protesters turned out in Sydney on Sunday to highlight the threat of mass starvation facing two million Gazans and call for the Australian government to sanction Israel.

Prof Rothwell said the effectiveness of Mr Albanese's statement on its own would be limited, but repeating the claim in front of the UN General Assembly in September or pursuing economic sanctions against Israel could carry greater weight.

Despite his growing criticisms of Israel, Mr Albanese said Australia would not follow the lead of France in "imminently" recognising Palestinian statehood at the General Assembly.

Any resolution would need to guarantee Hamas, the de facto ruling authority in Gaza listed as a terrorist organisation by Australia, had no part in Palestine's future, he said.

"We need security for the state of Israel, but you need to have the legitimate aspirations of the Palestinians for their own state realised as well," Mr Albanese said. 

"That will mean security arrangements, it will need agreements as well about the rebuilding of Gaza and the West Bank. It will need the issue of settlements to resolve as well."

Recognising a Palestinian state as part of a two-state solution in the Middle East is included in Labor's national platform.

"Are we about to imminently do that? No, we are not," Mr Albanese said.

"But we will engage constructively. The United States as well will have a critical role in this. They have to play a role."

Mr Albanese once again called for an immediate ceasefire and for Gaza to release Israeli hostages.

But opposition foreign affairs spokeswoman Michaelia Cash said the government had failed to lay the blame for the war at the feet of Hamas in a statement condemning Israel's denial of aid.

Australian Associated Press