Prime Minister Tony Abbott has confirmed a potential terrorist threat against Parliament House, saying there is “no doubt” there was “chatter amongst these networks of targeting government people”.

Mr Abbott told the TODAY show a review of security at Parliament House has been undertaken.

“One of the first consequences ... has been moves to put the Australian Federal Police back in charge of internal, as well as external security,” he said.

The revelations follow yesterday’s dawn raids on a number of suburban Sydney homes after national security officials received information that Islamic extremists were plotting a horrific random attack on an Australian citizen.

So far, two men have been charged after the operation, the largest of its kind in Australian history.

Senior intelligence figures were quoted in News Corp confirming they had overheard “chatter” indicating Parliament House was a potential target for an attack similar to that on Mumbai in November, 2008.

It was not clear whether the threats were directly related to the arrests yesterday.

Australian security forces have reportedly identified a “weak spot” in a Parliament House wing, currently defended by only two unarmed guards.

Overpowering them would give intruders a direct line to the Prime Minister’s private courtyard.

Other security measures being considered for Parliament House include increased safety barriers and airport-style security checks for visitors.

The Prime Minister said Australia remains a “safe country” but did not rule out more raids, saying “there are people even here in Australia that will do us harm”.

“There is no doubt that there are small networks of people in this country who are in regular contact with senior ISIL operatives in Syria and Iraq who would do us harm if they could.

Timeline of Sydney's early morning terror raids View Gallery

“As soon as the police and security agencies have evidence that any activity is likely, they will act,” he said.

Mr Abbott said it is paramount our authorities stay “at least one step ahead” of terrorists.

“I have great confidence in the professionalism and commitment and the skill and capacity of our police and security agencies,” he said.

Mr Abbott refused say Australian forces were being sent to Iraq to take part in a “war” but said “we are ready to do what we must”.

“We are well and truly prepared for combat operations inside Iraq,” he said.

“As we saw on the streets of Sydney yesterday, this conflict is reaching out to us.