"We have no evidence that this is an attempt to influence the outcome of parliamentary processes or to disrupt or influence electoral or political processes", the presiding officers of the bicameral parliament said in a statement, as quoted by ABC.
There is no evidence that any data has been accessed, but the investigation remains ongoing, Speaker Tony Smith and Senate President Scott Ryan said in a joint statement this morning.
In December, officials in the United States and Britain said businesses and government agencies in the two countries and at least 10 others - which did not include Australia - were the victims of a massive data theft carried out by state-sponsored Chinese hackers.
As a precaution, all passwords have been reset and users forced to set new ones.
The Australian Signals Directorate (ASD) is working to secure the network and says action was taken as soon as the breach was detected.
Addressing reporters on Friday, Prime Minister Scott Morrison likewise declined to speculate about the identity of the attacker, and he reiterated that the attack appeared to be limited to targeting Parliament's network.
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Parliament House in Canberra, Australia.
The incident has been compared to a robber breaking into a house, whereby authorities know the front door has been broken but are yet to find out if anything else has been taken, or if there is another way to break in.
Labor politicians and staff said access to their emails had been intermittent since the attack.
Opposition Leader Bill Shorten says the breach - which he was confident was being handled properly - is a "wake up call".
The incident hit the parliamentary computing network and resetting passwords to all of those with network access is one of the "number of measures" the DPS has implemented to protect the network and users.