Australia's consumer price index (CPI) is expected to rise 0.4% in August from the previous month, which would increase the annual pace of inflation to 4% from 3.5% in July, Westpac said in a Monday report.

The bank expects a 0.7% monthly CPI increase on a seasonally adjusted basis.

Meanwhile, the August trimmed mean measure of underlying inflation is expected to rise 0.2%, down from the 0.4% average over the previous three months and holding the annual pace steady at 3.6%, the bank said.

Westpac also revised its CPI estimate for the third quarter to 1.3% from 1.1% previously, and now expects the quarterly trimmed mean to print at 0.9%, compared with a previous call of 0.8%.

"A stronger-than-expected July set a higher starting point which we expect to be partially unwound in August-September," the bank said, adding that it still foresees a moderation in the fourth quarter with the trimmed mean reading expected at 0.7%.

Westpac now sees annual headline inflation at 2.4% by the end of 2027 and at 2.3% by the close of 2028, noting that its year-ended estimates are below the Reserve Bank of Australia's current forecasts.