Australia Post has admitted contacting the City of Melbourne and Pauline Hanson after more than 100 One Nation-branded stubby holders were not delivered to locked-down public housing tower residents.
But the agency denies its chief executive threatened the council or contacted Senator Hanson directly about the hold-up.
Senator Hanson dispatched the 114 stubby holders in July with a note that read: "No hard feelings."
Days earlier, she labelled residents of the Melbourne towers drug addicts and alcoholics, claiming they were from war-torn countries and English was probably their second language.
Council officials overseeing the government-enforced lockdowns intercepted the parcels and decided against delivering them, concerned they could further inflame tensions.
In an email first published by the Nine newspapers, Australia Post warned the council it would notify the police unless the parcels were delivered without delay.
Australia Post claimed this did not amount to a threat and denied chief executive Christine Holgate personally intervened.
At the time, One Nation senators were considering whether to vote in parliament in favour of overturning a temporary relaxation of postal delivery rules.
"Australia Post confirms that Ms Holgate did not speak to Senator Hanson or One Nation on this matter, nor did she threaten Melbourne City Council," the agency said in a statement on Thursday.
But the agency confirmed it contacted both the City of Melbourne and Senator Hanson about the matter.
Australia Post said the agency took its obligation to deliver mail seriously.
"Upon subsequently being made aware the items did not reach their ultimate destination, we raised it with the City of Melbourne and engaged with the sender (Senator Hanson) in good faith to resolve the matter," it said.
"Commonwealth laws prohibit any conduct which interferes with the mail, and make it clear that Australia Post is obliged to complete the delivery of Australians' mail to the designated address."
Senator Hanson dismissed the controversy and used it to market more One Nation merchandise.
"Talk about a storm in a stubby cooler," she said.
Australian Associated Press