Iron ore inventories at ports in China, the largest importer of the steel-making raw material, fell totheir lowest level in almost 11 months on Tuesday, as mills replenished holdings after prices felland local output slowed during the winter.

The stockpiles dropped 0.9 percent to 100.6 million tons by Jan 2, shrinking for a sixth week,according to data from Shanghai Steelhome Information Technology Co.

That is the lowest level since February last year, and the sixth weekly decrease is the longest runof declines since April 2013. The inventories are 12 percent lower after peaking at 113.7 milliontons in July.

While iron ore retreated 47 percent last year as global output expanded, prices opened 2015with the biggest weekly gain in 18 months amid speculation China will take more steps to spurgrowth.

The country is accelerating infrastructure projects valued at 7 trillion yuan ($1.1 trillion), accordingto industry sources. Some ore mines in China typically close during the winter, and last year'sslump in prices spurred speculation that not all of them will reopen this year.

"Restocking by mills, plus the seasonal factor of northern Chinese mines closing for winter" drovethe stockpiles lower, said Philip Kirchlechner, director of Iron Ore Research Pty in Perth,Australia, adding that if the mines stay shut after the winter, it "is a possible sustaining factor forprices".

Ore with 62 percent content delivered to Qingdao retreated 0.6 percent to $70.87 a dry metricton on Monday, the first decline in seven sessions, according to Metal Bulletin Ltd. The price－which fell to $66.84 on Dec 23, the lowest level since June 2009－rallied 5.8 percent in theweek to Jan 2.

Data on Tuesday showed that shipments of ore to China from Australia's Port Hedland, theworld's biggest bulk-export terminal, rose in December after Brazil said on Monday it exportedthe most iron ore in the same month since 2005.

Exports through Port Hedland for China reached 30.6 million tons from 29 million in November,according to port data. Exports through the port to all countries in 2014 surged to 414 million tonsfrom 318 million tons in 2013, according to Bloomberg calculations.

Many high-cost mines in northern China that shut over the winter may not resume production thisMarch, Citigroup Inc said in a Nov 11 report.

Local output will drop 30 percent to 236 million tons this year, HSBC Holdings Plc said on Oct22.

The stockpiles at Chinese ports were 13 percent above the five-year average of 89.04 milliontons, according to Bloomberg calculations. The country produced 19 percent more crude steel inthe first 11 months of last year than all of 2010, data by the World Steel Association show.

China's economy is likely to have expanded in 2014 at the slowest pace since 1990 as growthwas constrained by a housing slump and factory-gate deflation. The world's second-largesteconomy, which cut interest rates in November, buys two-thirds of seaborne ore.

The government approved the acceleration of 300 projects this year as part of a broader 10trillion yuan plan to run through 2016, according to industry sources. The investments will beacross seven industries including oil-and-gas pipelines, transportation and mining, according tothe people.

"Chinese end-user demand will remain pretty soft," said Ivan Szpakowski, an analyst at Citigroupin Hong Kong, during a Bloomberg Television interview.

"Over the course of the year, supply will be increasing very strongly. We see prices falling into the$50s."

Shipments from Brazil, the biggest exporter after Australia, rose 18 percent to 37.4 million tons inDecember from a year earlier, according to data on Monday. That is the highest level in at leastnine years as Vale SA boosted output.