China's house prices fall further, economic gloom deepens

* Home prices extend declines, further drops expected

* Cooling property market main risk to economy

* More stimulus expected but may hinge on health of job market

* Central bank steps in again as downside risks grow

By Xiaoyi Shao and Lu Jianxin

BEIJING/SHANGHAI, Sept 18 (Reuters) - Worries that China's economy may be slowing further intensified on Thursday as data showed home prices fell for the fourth straight month, adding to expectations that Beijing will need to do more to stimulate activity.

For now, policy easing is likely to come in the form of help to the most vulnerable sectors, rather than more aggressive steps such as cutting interest rates, but authorities are ready to step in with bolder measures if unemployment rises, policy insiders told Reuters.

China's central bank reportedly stepped in this week to avert any further shocks to the world's second-largest economy.

The People's Bank of China offered to lend $81 billion to big banks to reduce the risk of a credit crunch and a jump in interest rates heading into the long "Golden Week" holidays in early October, when demand for cash typically soars.

Despite the move, short-term lending rates dipped only briefly on Thursday, and traders said borrowing costs will start to rise again soon unless the PBOC continues to pump money into the system, highlighting growing nervousness in the market.

"Chinese authorities will likely introduce more supportive policies, including favourable tax and mortgage policies, before the end of this year to ease the downward pressures on the property market," ANZ economists Liu Li-Gang and Zhou Hao said.

"We thus expect more monetary policy easing in the remainder of this year, if the upcoming data continue to remain lukewarm. We cannot discount the possibility of an outright 50 basis point RRR cut (in bank reserve levels) for the whole banking system, or even a policy rate cut."

Analysts at Barclays were even more certain that policymakers will have to administer stronger medicine soon.

"Interest rate cuts are inevitable," they said in a note to clients, adding that the central bank's decision to lower the yield for its 14-day repos by 20 basis points on Thursday was a sign of the times.

"Today's move sends a clear and strong signal, in our view, that the People's Bank of China is more convinced that it needs to make more effort to guide interest rates lower," Barclays said. It predicted two interest rate cuts of 25 basis points each between October and March 2015.

Lower rates could arrest the cooldown in China's once red-hot property market, where fizzling growth is increasingly dragging on the broader economy, sapping demand for housing-related products from appliances and furniture to cement and steel.