Australia's biggest political parties compromised in IT breach

Australia's three largest political parties were hit by a malicious intrusion of Parliament House's network by a suspected state-sponsored attacker, the prime minister has confirmed.

Scott Morrison addressed the lower house on Monday morning to discuss the investigation into a security incident two weeks ago, which forced all 4000 parliamentarians and staff to reset their passwords.

"During the course of this work, we also became aware that the networks of some political parties - Liberal, Labor and the Nationals - have also been affected," Morrison said.

Morrison seemed to back up previous ABC reports claiming the intrusion was likely the work of a foreign government attack, but Australia's security authorities are yet to confirm those reports directly.

"I do not propose to go into the detail of these operational matters. But our cyber experts believe that a sophisticated state actor is responsible for this malicious activity."

Morrison looked to quell any fears of electoral tampering, adding that there was no evidence of any electoral interference, saying a number of measures had been put in place to ensure the system's integrity.

"I have instructed the Australian Cyber Security Centre to be ready to provide any political party or electoral body in Australia with immediate support, including making their technical experts available."

"They have already briefed the Electoral Commissions and those responsible for cybersecurity for all states and territories. They have also worked with global anti-virus companies to ensure Australia’s friends and allies have the capacity to detect this malicious activity."

Morrison reiterated the government's decision to act proactively about the intrusion.

"Our political system and our democracy remains strong, vibrant and is protected.  We stand united in the protection of our values and our sovereignty.

"The government has chosen to be transparent about these matters.  This in itself is an expression of faith by our Government in our democratic system and our determination to defend it."