Text messages to voters about an intercepted asylum seeker boat on election day were sent without the approval of the outgoing home affairs minister Karen Andrews.
The new Labor government has labelled the move a "disappointing" example of the Liberal-National coalition politicising border protection.
But Ms Andrews said text messages sent by the Liberal Party on Saturday were not approved by her.
"I had no knowledge of the text messages. I didn't know that they were being even contemplated," she told the ABC on Wednesday.
"A lot of things were happening on election day. What the party chose to do is a party matter ... it wasn't something that was endorsed by me."
The text from the Liberal party had read: "BREAKING: Australian Border Force has intercepted an illegal boat trying to reach Australia. Keep our borders secure by voting Liberal today. https://vote.liberal.org.au".
It came after Border Force released a media statement on election day stating that a vessel had been intercepted.
"A vessel has been intercepted in a likely attempt to illegally enter Australia from Sri Lanka," Joint Agency Task Force Operation Sovereign Borders commander Rear Admiral Justin Jones said.
"The Australian Government’s policy remains unchanged. We will intercept any vessel seeking to reach Australia illegally and to safely return those on board to their point of departure or country of origin."
Ms Andrews defended the Border Force media release about the boat intercepted in Australian waters as "operationally focused".
"It was actually an important thing to do, given the fact that it was election day and there needed to be transparency," she said.
But Treasurer Jim Chalmers said the former government breached the bipartisan approach to border protection in a last-ditch effort to sway voters.
"We've communicated our displeasure at the publication and politicisation of that boat ... on election day," he told the ABC.
"We shouldn't be dealing with border security in that fashion."
Labor calls for investigation into boat intercept disclosure
Deputy Prime Minister Richard Marles on Tuesday revealed he had requested the secretary of the Department of Home Affairs to report back to the government on the circumstances of the information being made public on election day, describing it as "not routine".
"What's really clear is that the former Liberal government was far more interested in its own political interests than in the national interest," he told Sky News.
"It sought to create division where there was none. Everyone knew that there was bipartisanship in relation to maintaining strong borders and that is a national asset.
"But what that government did was seek to undermine that for its own political purposes."
Mr Marles vowed the Albanese government would not use matters of national security for "political gain" and would act in the national interest.
The Labor government also revealed on Tuesday that it had turned around its first asylum seeker boat.
Border security had been a repeated point of tension during the election campaign with the Coalition claiming it was more qualified to manage this policy because of its record of turning back boats during its time in government.
But Labor has insisted they are committed to upholding the same boat turnback approach as demonstrated by its early action in power.
