Spot iron ore should stay in a range of $120 to $170 a metric ton for the next three months after steelmakers in China, the biggest buyer, increased prices of their products, said National Australia Bank Ltd.

“The really volatile period seems to be over for iron ore for now, with the price leveling off,” said Michael Bush, Melbourne-based head of fixed income and credit research at the bank. “The price will be range bound, with a floor of $120 and a top of $170. It will probably spend most of the next few months between $130 and $150.”

Baoshan Iron & Steel Co., China’s biggest publicly traded steelmaker, yesterday increased cold-rolled coil prices for the first time in three months because of higher costs. Iron ore for immediate delivery to the Chinese port of Tianjin fell 0.9 percent yesterday to $138.30 a ton, data compiled by The Steel Index Ltd. show. That’s down 1.1 percent from the week before.

Iron ore prices, which tumbled 31 percent in October in the biggest monthly loss since December 2008, rebounded 11 percent in November as mills replenished stockpiles.

Imports of the steel-making ingredient by China surged 29 percent to 64.2 million tons in November from an eight-month low, data on the General Customs website posted on Dec. 10 show. That’s the highest since January and compares with 49.94 million tons in October, according to Bloomberg data.

January-delivery prices of cold-rolled coil used in automobiles were raised by 100 yuan ($16) a ton, Shanghai-based Baoshan said in a statement on its trade website, without giving details. That’s the first increase since October, data compiled by Bloomberg show. The company kept January prices of hot-rolled coil unchanged.

Iron ore prices have “usually” reacted to news of Europe’s debt crisis this year, National Australia’s Bush said. “The price of ore will stay a bit choppy for at least the next three months but won’t be too volatile,” Bush said.