· In short: A Labor backbencher has broken ranks with her party to label Israel's actions in Gaza as "genocide".

· Senator Fatima Payman also challenged the prime minister to take action, including sanctions on Israel.

· What's next? The prime minister avoided responding to the backbencher in an interview late on Thursday.

Labor Senator Fatima Payman has broken ranks to accuse Israel of carrying out "genocide" in Gaza, calling on her party to sanction and cease trade with Israel.

"My conscience has been uneasy for far too long, and I must call this out for what it is," Senator Payman told SBS News.

"This is a genocide, and we need to stop pretending otherwise."

Senator Payman directly put questions to Prime Minister Anthony Albanese and her other colleagues, asking them to "stand for what is right".

"I ask our prime minister and our fellow parliamentarians: how many international rights laws must Israel break for us to say enough? How many lives does it take to call this a genocide?" Senator Payman asked.

"I see our leaders performatively gesture defending the oppressors' right to oppress while gaslighting the global community about [Israel's] rights of self-defence."

Israel has repeatedly denied claims of genocide, which is defined under international law as killing or harming members of a national, ethnical, racial or religious group with "intent to destroy, in whole or in part".

A contentious case launched by South Africa in the International Court of Justice (ICJ) accusing Israel of genocide has not made any finding, but the court ordered Israel to take all measures within its power to avoid killing or harming Palestinian civilians.

The ICJ said accusations of genocide were plausible, but a finding could take years to be made.

The federal government has become increasingly critical of Israel's behaviour in Gaza, particularly after an Israeli air strike killed Australian aid worker Zomi Frankcom and several other charity workers travelling in a marked van.

But it has not supported accusations of genocide, and when challenged on ABC Radio about Senator Payman's comments, Mr Albanese avoided a direct response.

"We've called for the release of hostages. We've also voted for — in the United Nations, going back a long period of time — we have voted for cessation of hostilities for that to occur. We've called for humanitarian assistance. We have said very clearly that all lives matter, whether they be Israeli or Palestinian," Mr Albanese told the ABC.

"We've called for and voted for, just last Friday, increased participation of Palestine in the United Nations."

He added that the government had consistently supported a two-state solution to the conflict.

Defence Minister Richard Marles told the ABC "genocide" was not a word he would use in relation to Gaza, but that it was an "absolute tragedy".

The ABC has contacted the embassy of Israel for comment.

Senator Payman's comments were made on the anniversary of the Nakba, marking the mass displacement of Palestinians during the 1948 Arab-Israeli war, and amid escalating tensions on university campuses where students have held encampments in protest of the war.

She added "indecisiveness" was undermining Australia's multicultural values and social cohesion.

"We cannot be disconnected from the people of Australia, the young of this nation are telling us and we are silencing them. The future of this nation is speaking, and we are silencing them instead of advocating for justice," Senator Payman said.

"The lack of clarity, the moral confusion, the indecisiveness is eating at the heart of this nation. It is dividing and confusing the nation."

The senator ended her remarks with the pro-Palestinian phrase "from the river to the sea, Palestine will be free", which Mr Albanese said last week was an anti-Israel chant that ran contrary to goals for a two-state solution.