* China looking at cutting 25 pct tax by up to half
* Move may lead to lower iron ore prices
* Plan may be opposed given potential revenue loss
By Ruby Lian and Manolo Serapio Jr
SHANGHAI/SINGAPORE, Nov 23 (Reuters) - A proposed tax cut by China for its iron ore miners could lead to lower prices of the raw material, but it is unlikely to reduce imports by the world's top buyer as it does little to improve the competitiveness of domestic producers.
China may also face strong opposition to the plan to drop the total tax rate for local iron ore miners to 10-15 percent from 25 percent because of the potential revenue loss for local governments, industry officials and analysts say.
China is the world's biggest producer of the raw material, with an annual output of more than 1 billion tonnes. But the low quality of its iron ore means it relies heavily on imports.
It buys about two-thirds of globally traded iron ore, with this year's imports of the steelmaking raw material expected to top last year's record 686 million tonnes.
The proposed tax cut will "not make one iota of difference" in China's iron ore imports, said Rory MacDonald, an iron ore broker at Freight Investor Services (FIS).
Other analysts agreed, saying the move to cut taxes would also not change China's status as one of the world's most expensive iron ore producers.
"Given China's place at the top of the global cost curve, reducing cost support through lower taxes will only mean that prices fall, leaving the domestic producers in the same position as before the tax cuts," said Graeme Train, commodity analyst with Macquarie in Shanghai.
Production cost will be cut by $12 per tonne at the top of the curve if the overall tax rate is chopped to 10 percent, Train said.
Chinese miners, whose margins have been squeezed by higher energy, labour and environmental costs, spend between $90-$130 to produce a tonne of iron ore, compared to $30-$50 per tonne for big producers in Australia and Brazil.
"It's just a retrospective nod by the government to lighten their load a bit after what's been a tough year and a half. I don't see them passing it on to pricing, they'll embrace it potentially to widen profit margins," FIS' MacDonald said.
MORE VULNERABLE TO PRICE VOLATILITIES
A forecast drop in global iron ore prices over the next three years as top overseas miners ramp up output while Beijing's steel output growth slows will also negate any benefit from China's planned tax cut.
Even with iron ore prices unlikely to return to record levels of near $200 per tonne reached last year, the still big margins enjoyed by low-cost producers Vale, Rio Tinto <RIO.AX RIO.L> and BHP Billiton mean they can go ahead with plans to boost output, although they are holding off on longer-term strategies.
"I don't think China can cut reliance on seaborne supplies priced off spot indices by growing its domestic iron ore industry. It only can really achieve a decrease in reliance on seaborne supplies by purchasing mining assets overseas and shipping the material back home," said FIS' MacDonald.
With thinner margins, Chinese miners are also more vulnerable to price volatilities than their overseas rivals. Some of them have been forced to shut in recent months when prices slumped to three-year lows below $87 a tonne . Prices have since rebounded to around $120.
Still, with local governments already struggling with falling revenues on a slower economy, there are doubts on whether the tax cuts could be rolled out.
"There are various taxes and many parties are involved. It's still hard to predict which tax could be cut, which not," said an official from industry group China Iron and Steel Association who declined to be named as he was not authorised to speak to media.
"However, they may have to make compromises eventually if local mines are not able to maintain business."