Australia's Westpac-Melbourne Institute Consumer Sentiment Index fell 5.2% to 84.4 in September from 88.9 in August, as higher fuel prices, rate rise fears and a housing downturn weighed on consumers, according to a Tuesday report by Westpac.

The bank said the sub-index tracking family finances versus a year ago dropped 9.2% to 72.6, giving back almost all of August's gain, while the family finances next 12 months sub-index fell 3.9% to 94.5, and the Mortgage Rate Expectations Index rose 7.3% to 170.4, with nearly two in three consumers expecting mortgage rates to rise further over the next 12 months.

The Unemployment Expectations Index rose 2.8% to 139.4, marking a further marginal deterioration, with construction and hospitality workers among those most uneasy about job security, while the time to buy a dwelling index dropped 10.7% to 85.5, giving back all of last month's rally, the report added.

Westpac said that while the strong July consumer price index reading increases the chances of a future rate hike, it believes the RBA Monetary Policy Board is unlikely to move based on one monthly inflation read, especially with the next consumer price index update set for release a day after the meeting, it added.