Australian Defence Force (ADF) troops could not have been deployed faster to flood-affected areas in NSW and Queensland, according to Defence Minister Peter Dutton.
As the government comes under criticism for its response times in dealing with the flooding crisis, Mr Dutton said state emergency services in both states had been overwhelmed by the situation.
"We had people pre-positioned, we had assets pre-positioned. The planners looked at the circumstances both in Queensland and NSW, they made judgements about where they were moving people to," he told the Nine Network on Friday.
"We have increased gradually as we have been able to access areas in NSW, it has been an easier undertaking in the south-east corner (of Queensland)."
Prime Minister Scott Morrison said more support would be provided to both states.
Mr Morrison will meet with Governor-General David Hurley later on Friday to advise him on declaring the first national emergency.
The declaration will be made despite Queensland Premier Annastacia Palaszczuk indicating the state would not need the measure.
Mr Dutton defended the decision not to declare the national emergency sooner.
"The obviousness that's there now with 20/20 hindsight isn't there in the opening hours," he said.
"They are isolated communities where they don't have telecommunications, they haven't been able to even call the police to report their circumstances or the fire brigade or a rescue organisation like the SES."
The prime minister said there had been a misunderstanding over the impact of the national declaration, which would have nothing to do with the flow of funding.
The national declaration would allow the Morrison government to access stockpiled resources and remove red tape in terms of business and welfare support.
It's the first time such a declaration will be made, with the law only coming into effect in 2020 following the Black Summer bushfires.
Labor's deputy leader Richard Marles said there had not been any criticism of the work the ADF had been undertaking, but rather the government's response.
"There was the ADF on the ground, they were doing a great job, SES, police. What there wasn't was the coordination of all of that," Mr Marles said.
"It's in that sense that the declaration of the state of emergency has come too late, it really should have happened a week ago so that leadership could be in place."
Almost 6000 ADF troops are assisting with the clean-up.
The Insurance Council of Australia has estimated the damage bill from the floods to be more than $1.7 billion, with that figure expected to rise.
More than 118,000 claims have been made following the disaster, of which 44,193 were from NSW and 73,823 were in Queensland.
