Anthony Albanese’s promise to give full cooperation to inquiries into the Bondi Beach terror attack is in question after accusations Labor has used Cabinet confidentiality to hide key information.

The Prime Minister had called a Royal Commission into Anti-Semitism and Social Cohesion in January after sustained pressure in the wake of the December 14 massacre of 15 people at a Hanukkah event.

He had vowed the Government would “fully cooperate” with the investigative process, however, it was revealed this week that Labor had asserted public interest immunity over critical information.

The claim to keep details confidential could prevent Royal Commissioner Virginia Bell from examining whether Cabinet directed Australia’s spy agency to put fewer resources into counterterrorism in the lead up to the attack.

Shadow Home Affairs Minister Jonno Duniam on Friday accused the Government of using Cabinet-in-confidence to “shield” from embarrassment

“We are dealing with the largest terrorist event in our country’s history — the Government made decisions and we need to know exactly what those decisions were,” Senator Duniam told Sky News.

“I cannot see how who made the decision relating to funding and resourcing of intelligence agencies is something that should be held back from consideration by the royal commissioner.

“I hope that the Government does the right thing and doesn’t hide this information from the public.”

Opposition Leader Angus Taylor accused Mr Albanese of lying again to the Australian public after pledging his government would fully cooperate.

“They don’t want to come clean about how they’ve gutted counter-terrorism funding in this country,” he said on Friday.

“As always with this Government, they never want to come clean.”

Australia’s Attorney General sought to defend the government in a radio interview on Friday, insisting that exercising the gag mechanism was business-as-usual.

“There’s nothing that the Commonwealth’s doing that is novel in terms of there being Cabinet confidentiality,” Michelle Rowland said.

“It’s a well-established legal principle that Cabinet documents and information of that nature attract public interest immunity in legal proceedings and Royal Commissions.

“But it’s important also to note the decisions about whether to disclose Cabinet information are ultimately a matter for the Commissioner.

“Commissioner Bell can see this information and can release it, she has the authority to do so.”

The head of spy agency ASIO Mike Burgess revealed that Labor had sought to assert public interest immunity in a written statement to the Royal Commission earlier this week.

ASIO deputy director-general Lisa Alonso Love had confirmed in a Senate Estimates hearing on Thursday evening that the intelligence agency did not seek the order to gag details relating to its resources.

“That wasn’t something that ASIO has asked for, it would be a question you’d have to direct to the Department of Prime Minister and Cabinet,” she said.

Labor Senator Murray Watt then confirmed in the same hearing that the order had been sought by the PM’s department.

“All I can say is that the PII (public interest immunity) claim was made by the Commonwealth on advice from the Prime Minister and Cabinet Department for their Cabinet process but of course, the Royal Commissioner makes the final call on PII claims,” Senator Watts said.

Senator Duniam, however, argued there was “no justification” for the blocking of information, especially in regard to a probe which will examine the nation’s worst terror attack.

“This is not business as usual,” he said.

Mr Taylor reminded Australians it took the Prime Minister 25 days after the massacre of sustained calls for a high-profile probe.

“The Prime Minister never wanted a Royal Commission. That’s the point. He never wanted it because he knew what the outcome would be,” Mr Taylor said.

Mr Albanese had appointed former High Court justice Virginia Bell to examine the circumstances of the attack and broader social cohesion.