Concerns were raised following reports the Corpuls 3 and 3T devices, carried by NSW ambulances, encountered thousands of malfunctions in recent years.
The Therapeutic Good Administration issued a temporary halt on their sale following reports the devices were unexpectedly shutting down and rebooting during use.
But in a statement released Wednesday, the regulator stressed the defibrillators were still safe to use, noting it had not issued a recall of the devices.
The measures were precautionary and bought more time to investigate the failures, the TGA said.
"When there are issues or concerns, the TGA has compliance and enforcement powers such as imposing conditions on the supply of products and suspending or removing products from supply," the statement said.
"While the suspension is in place, existing devices already in ambulances and healthcare facilities can continue to be used and serviced, but no new devices can be supplied."
The regulator stopped short of explaining exactly what caused the suspension, with Health Minister Ryan Park telling reporters he too wanted that information.
"They've made a decision not to disclose the details around that. That can be a little bit frustrating," Mr Park said.
"I'm going to see if we can access the reasons why."
Mr Park stressed there had been no reports of deaths of serious harm caused by failures of the devices in NSW.
"I want to be clear, the TGA has not told us to remove these devices," Mr Park said.
"I'm not going to pretend that this tool, like many other tools, have been without challenges for paramedics."
Nine Newspapers reported on Tuesday the devices had recorded 1229 failures in 2025 alone.
NSW Ambulance executive director of clinical capability Alan Morrison said failures could have been a range of things.
"The span of things that are reported in those technical issues go from clips and clamps to connectors," he said.
"We're not talking about a large number of defibrillation failures."
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