An artificial intelligence agent developed by OpenAI "infiltrated" an Australian government website in June, Prime Minister Anthony Albanese has said.

The agent hacked a statistics portal containing "non-sensitive" data from Australia's universal healthcare scheme, Medicare, Albanese said in New York on Wednesday, local time.

He had a "very frank discussion" with OpenAI CEO Sam Altman for taking "too long" to tell them about the breach, believed to be one of the world's first publicly reported AI-led hacks of a government website.

OpenAI said it only became aware of the incident in August "during an ongoing review" of "misaligned model activity", and told Australian officials on 10 September.

While the review is ongoing, OpenAI said in a statement that it is not believed any patient records were accessed.

Albanese said the breach occurred in June this year, but OpenAI only informed Services Australia - the national hub directing users across government services - via email on 10 September.

The agency contacted the relevant minister who passed on the information to the prime minister at the weekend.

Albanese said he had also expressed "Australia's extreme concern about this incident" when he spoke to Altman, and there will "obviously be legal consequences for it".

Altman, the prime minister, said he acknowledged there were "issues with protocols" at OpenAI.

Albanese said the agent accessed both public and non-public files, and a "forensic investigation" is underway to determine whether other government systems were affected.

The investigation will be led by the Australian Signals Directorate, the country's cybersecurity agency.

The public-facing Medicare Statistics Reporting Service portal, which was hacked, is administered by Services Australia.

Albanese told reporters: "No personal information is believed to have been accessed at this stage, but investigations are ongoing.

"Evidence currently available is that there is no broader compromise to the Services Australia network. Nonetheless, this situation is obviously unacceptable."

Albanese declined to answer whether he raised the matter with US President Donald Trump during their face-to-face meeting on Tuesday night in New York, where world leaders have gathered for the UN General Assembly.

Earlier this year, OpenAI revealed a group of AI agents it had been testing had escaped from their controls and secretly worked together to hack another tech firm named Hugging Face.