He said that the government now expects to pay 99.1 billion Australian dollars (67.4 billion U.S. dollars) in interest on repayments for the record debt over the next four years.
It represents an increase of 13 billion AUD (8.8 billion USD) from the 86.1 billion AUD (58.6 billion USD) forecast in March.
The March budget, which was handed down by former Treasurer Josh Frydenberg, projected gross government debt would peak at approximately 45 percent of gross domestic product (GDP) in 2025.
However, it assumed interest rates on government debt would average 2.2 percent over the next four years.
Chalmers said rates were averaging 3.5 percent.
"Just like millions of Australian families who now have to dig deeper into their pockets to make their mortgage repayments, rising interest rates are also having a significant impact on the government's bottom line," he was quoted by Nine Entertainment newspapers as saying on Monday.
"Every dollar of borrowing in the budget now costs more to service. It's more important than ever that the government is responsible with taxpayers' funds."
Chalmers, who became Treasurer when the Labor Party won May's election, will give an update on the economy when Parliament returns on July 26 before handing down his first budget in October.
"The October budget will be all about responsible cost-of-living relief, implementing our economic plan and redirecting money wasted by our predecessors to more productive investments," he said.
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