Malcolm Turnbull insists his new super security ministry will make Australia safer but Labor wants him to show how.
The prime minister is spruiking his decision to combine national security agencies into one home affairs umbrella overseen by Peter Dutton.
Asked on Wednesday if the merger will make Australia safer, Mr Turnbull told the Nine Network: "Yes, it will".
"Set and forget has no place in national security. Complacency has no place in national security," he said.
Mr Turnbull said the shake-up, modelled on the UK system, was long overdue and would be done if Australia's security network was being designed from scratch.
"I don't need a crisis to cause me to act," he later told Triple M.
He refused to be drawn on whether Mr Dutton's new appointment was a way of pacifying the conservative, saying it was disappointing to see people trying to put a "political gloss" on the announcement.
"The only issue here is the safety of all Australians," Mr Turnbull said.
Shadow attorney-general Mark Dreyfus remains unconvinced.
"As yet the government has not explained how it is that this very substantial change to our national security arrangements is going to indeed make Australians safer," he told ABC radio.
Mr Dreyfus said to his knowledge ASIO and other agencies did not call for the changes.
Opposition Leader Bill Shorten spoke to Mr Turnbull on Tuesday night and said the party would not stand in the way of the changes but wanted advice from experts.
"We will work constructively with the government but they've announced what they say is the biggest overhaul in 40 years," he told reporters in Sydney.
"Where is the problem to justify the biggest overhaul in 40 years?"
Mr Dutton, who takes over ASIO, the Federal Police and Border Force, said the portfolio would make Australians safer because his sole priority as a cabinet minister would be national security.
He said agency heads were consulted and it was not done for political reasons.
"The prime minister has been mulling over this for a long period of time to make sure that we get it right," he told ABC radio.
"I believe we have got the balance right."
Mr Dutton did not have an estimate on how much the arrangement changes would cost but said he wanted to see more money on the front line.
