Australian banks may soon introduce tighter lending standards, which could push down house prices, the Reserve Bank says.

While not singling out fallout from the banking royal commission, Reserve Bank of Australia deputy governor Guy Debelle says there is a risk of further tighter lending standards on the horizon.

"This may have its largest effect on the amount of funds an individual household can borrow, more than the effect on the number of households that are eligible for a loan," he told a forum of chief financial officers in Sydney earlier this week.

"This, in turn, means that credit growth may be slower than otherwise for a time.

"To me, that has more of an implication for house prices, than it does for the outlook for consumption."

But Risk Wise property research chief executive Doron Peleg said a major price correction in Sydney and Melbourne is unlikely, especially given recent regulatory wind-backs.

"Taking into account the outstanding price growth across Sydney and Melbourne, we've only seen some small movements in the property market," he said.

Mr Peleg said banks' desire to grow their market share in the residential lending sector meant they had reduced interest rates not only for principal and interest home loans but also for interest-only investment loans after the Australian Prudential Regulation Authority in April lifted caps on lending to property investors that it introduced in 2014.

House prices across Australia's five major capital cities were flat last week with the number of auctions and the clearance rate down from the same period a year ago.

On a yearly basis, home prices were down 3.8 per cent in Sydney in the week ending May 13, while they were 3.3 per cent higher in Melbourne, 0.7 per cent higher in Brisbane and Adelaide and 2.2 per cent lower in Perth, data by CoreLogic property group shows.

Of the 2,245 homes that went under the hammer last week across the capital cities, just 61 per cent sold, down from 2,409 homes and a clearance rate of 72.8 per cent in the same week a year ago.

CAPITAL CITY PRIVATE TREATY MEDIAN PRICES:

Sydney - house $905,000, unit $680,000

Melbourne - house $736,00, unit $550,000

Brisbane - house $535,000, unit $385,000

Adelaide - house $445,000, unit $321,200

Perth - house $509,000, unit $395,000

Hobart - house $446,650, unit $380,000

Darwin - house $567,500, unit $375,000

Canberra - house $645,000, unit $411,600