Speaking on ABC's Insiders program, Chalmers said rapidly rising borrowing costs in Australia and other major economies would put "additional pressure" on the budget. Federal government debt recently passed $1 trillion, while spending is at its highest level in four decades outside the pandemic.
The Reserve Bank's decision to raise the cash rate to a 15-year high of 4.6 per cent last week has further limited fiscal space. Chalmers said the government would run a "pretty tight ship" in its mid-year update.
Chalmers attributed Australia's domestic inflation challenge partly to the war in the Middle East, which he said had "made much worse" the situation, and maintained his assessment was consistent with that of Reserve Bank governor Michele Bullock. He noted that over the past year, public demand had halved while private demand had tripled.
The Treasurer's comments come as internal pressure builds within Labor to restrain spending, with the mid-year budget update expected to reflect the tighter fiscal environment.