China's Anshan Iron and Steel Group is looking into a protest by American lawmakers against its deal to build steel plants in the US, a report said Monday.

"I'm aware of it. We are researching the situation and mulling how to deal with it," said Li Jiangyu, secretary to the president of the Chinese company, in answer to a question about the protest, Dow Jones Newswires reported.

Li added that company president Zhang Xiaogang would fly to the US today, but he didn't specify the reason for the trip.

The State-run Chinese steel manufacturer, also known as Ansteel, signed an agreement in May with US steel mill Steel Development Company that includes the construction of five plants in the US.

The first factory, to be built in Amory, Mississippi, will mainly target the southeastern US and Latin American markets, the company said previously.

A group of 50 US Congressmen last week wrote a letter to Treasury Secretary Timothy Geithner urging an investigation into the deal.

"We are deeply concerned that their direct investment in an American steel company threatens American jobs and our national security," the lawmakers said in the letter.

"We believe that this investment allows the full force and financing of the Chinese government to exploit the American steel market from American soil."

AFP's calls to Ansteel were not answered.