"If China would simply let the market work on its own we would have no objections, but their policies currently are preventing that from happening and they go against the very rules that China agreed to follow," Obama said.

Obama's comments came after the United States, European Union and Japan teamed up Tuesday to file a new World Trade Organization case against China's controls of the export of the rare earth materials.

His decision to publicly upbraid China from the White House Rose Garden may reflect the intense political heat he is facing on China trade issues as his reelection campaign unfolds against a fragile economic recovery.

But it is also in line with the fundamentals of his China policy that seeks cooperation with Beijing to ensure its peaceful rise, while being committed to holding the country accountable to global "rules of the road" in world trade.

"When it is necessary I will take action if our workers and our businesses are being subjected to unfair practices," Obama said.

"We want our companies building those products right here in America, but to do that, American manufacturers need to have access to rare earth materials, which China supplies."

The complaint formally requests "dispute settlement consultations" under WTO rules, the first step in any bid to settle trade disputes, according to EU trade officials.

It is the newest complaint by industrial powers at the WTO over Chinese trade in raw materials. In response to an EU complaint, earlier this year the Geneva-based body found China to have illegally restricted exports of raw materials such as bauxite, zinc or magnesium.