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* Jan-Feb property investment up 9.9 pct y/y, quickens from 2017
* Jan-Feb property sales 4.1 pct y/y, softer from year ago
* Jan-Feb new construction starts 2.9 pct y/y
BEIJING, March 14 (Reuters) - China's real estate investment over the first two months of 2018 grew at it strongest pace since 2015, with developers rushing to roll out new projects as a government crackdown on risky financing triggered worries about future financing.
But property sales growth softened from a year ago, data from the National Bureau of Statistics (NBS) showed, indicating efforts to stem speculation in the sector were paying off.
Real estate, which directly affects 40 other business sectors in China, is seen as one of the biggest risks for the country this year. A sharp softening of prices and investment would weigh on broader economic growth and consumer confidence, while a rebound in housing prices could trigger more government cooling measures, again threatening to curb growth.
Property investment grew 9.9 percent in January-February from the same period a year ago, data showed on Wednesday, the fastest growth for the period since 2015. It was also quicker than last year's 7 percent - which marked the best annual growth since 2014.
The number suggests "developers are speeding up development to launch more pre-sale projects," an analyst with Shanghai-based E-house China R&D Institute said.
"There might be growing liquidity pressure facing property developers," Yan Yuejin said in a note.
Some industry experts say signs of tighter liquidity have already emerged.
"Usually banks are more generous at the start of the year but this year it feels different," said Grant Ji, Executive director, Capital Markets, Northern China, CBRE.
Developers' financing cost has edged up at least 2 to 3 percentage points compared to last year, he added.
But the overall property sales growth, while softer, is not too pessimistic as smaller Tier-3 and Tier-4 cities are selling very well, he said.
SMALLER CITIES SELLING FAST
In a fierce war to boost market share, Chinese developers are planning a larger budget than last year to expand their land reserves and enter smaller cities as supply in bigger metropolises gets more difficult to find.
Some of China's provincial capitals have moved to support first-time buyers and upgraders by relaxing curbs, in a bid to lure talent and keep apartment sales booming.
China's property sales by floor area rose by 4.1 percent in January-February from a year ago, easing slightly from a 6.1 percent gain in December, according to Reuters calculations.
New construction starts measured by floor area were up 2.9 percent, after rising 8.6 percent in December, NBS data showed.
Some analysts say the figures are still more optimistic than expected, pointing to firm sales performance throughout the year as market expectations for small price appreciations are unlikely to be shaken.
A softening but still resilient property market would be good news for Chinese policymakers, who have stressed the need to avoid sharp price fluctuations, concerned about their impact on the world's second-largest economy.
China has set an economic growth target of around 6.5 percent this year, the same as 2017, while pressing ahead with a campaign to reduce risks in the financial system caused by riskier lending practices and a rapid rise in debt.
(Reporting by Kevin Yao, Lusha Zhang and Yawen Chen in Beijing; Clare Jim in Hong Kong; Editing by Himani Sarkar)