An executive from a real estate services company said on Thursday that a relaxation of mortgage rules in July hasn't so far helped the property market in the face of high interest rates, as she urged developers to cut prices to clear thousands of unsold homes.

Speaking on RTHK's Hong Kong Today programme, Hannah Jeong, head of valuation and advisory services at Colliers, said she was particular concerned by a six-year-low in the most popular sector of the market, for homes valued at HK$6 million to HK$10 million.

She was speaking after the Rating and Valuation Department reported a fourth consecutive monthly fall in home prices, which were down around 1.4 percent month-on-month last month.

"So if we look at one of the recent developments sold in the New Territories, in the first launch they were only able to sell 22 percent of their target number of units," Jeong told RTHK's Samantha Butler.

"So I think the developers need to adjust the price more reasonably to clear these accumulated units, because unsold units are exceeding 20,000 as of now. This is an extremely high rate. It's about 12 percent higher than December last year."

She said many buyers were holding off on purchases in the expectation that prices will slump further.

Jeong said she expects a further fall in prices of up to ten percent in the year ahead unless the government takes action to bolster the market, for example by withdrawing stamp duties introduced as a measure to cool the market in 2010.

The measures had been very good for curbing speculative activity, Jeong said, but buyers now understood there was little room to play the residential property market as an investment, and were now looking into it as a way of saving.

However she said the effects of removing stamp duty would depend on the movement of interest rates.