SYDNEY, July 1 (Reuters) - Home prices across Australia's major cities rose for a sixth straight month in June as falling mortgage rates kept demand hot in Sydney and Melbourne, a potential red flag for policy makers worried about the risk of a borrowing-fuelled bubble.
Friday's figures from property consultant CoreLogic RP Data showed its index of home prices for the combined capital cities firmed 0.5 percent in June, following very strong gains of 1.6 percent in May and 1.7 percent in April.
Growth for the June quarter was a brisk 3.8 percent while prices were up 8.3 percent on June last year.
The Reserve Bank of Australia (RBA) has long been concerned about an overheating housing market, but that did not stop it cutting interest rates to a record low of 1.75 percent in May after inflation proved much lower than expected.
The central bank holds its July meeting next week and is thought likely to stay on hold for the moment, though markets are wagering it could well ease again in August.
The RBA has noted that most of the heat is concentrated in Sydney and Melbourne with the rest of the nation more muted.
Indeed, values in Sydney jumped 1.2 percent in June to be 11.3 percent higher for the year, while Melbourne boasted gains of 0.8 percent and 11.5 percent.
In contrast, Brisbane saw a rise of 5.3 percent for the year, Adelaide 2.2 percent and Canberra 3.9 percent, while Perth suffered a fall of 4.7 percent. Home values outside the cities grew a bare 1.9 percent.
"Home values in Sydney have been rising for four years, and have increased by a cumulative 59 percent over this time frame," said CoreLogic's Asia Pacific research director Tim Lawless.
"Melbourne dwelling values have been rising for the same length of time and have moved 41 percent higher."
The median home price in Sydney is now A$780,000 ($581,000), far above the national level of A$580,000.
Such rampant inflation has made housing affordability a political flashpoint in an election campaign that ends this weekend, where the conservative government of Malcolm Turnbull holds a slender lead over the Labor opposition.
Labor has proposed "level the playing field" by ending tax breaks that favour borrowing to buy rental properties, a plan Turnbull claims would hurt home prices generally.