Forecasts the Reserve Bank could resume tightening interest rates next month

Westpac predicts the Official Cash Rate will rise by 25 basis points to 5.75 percent - after being paused last week.

Its chief economist says the bank will be motivated by inflation figures out this week and strong migration.

Kelly Eckhold says the population looks likely to grow 2.5 percent before year's end - the strongest since the 1960s.

He says there are some risks this could strengthen the economy and housing market, delaying inflation's fall.