Beijing has criticized Washington for agreeing to impose duties on imports of Chinese-made steel piping, the Wall Street Journal reported. A US trade panel also authorized the Commerce Department to investigate whether Chinese companies are selling Chinese-made coated paper and salted phosphate below market prices, a pratice known as "dumping". China has also begun its own investigation into whether cars imported from the US are being sold below market prices. The Chinese Ministry of Commerce said on its website that the investigation will look at sedans and sport-utility vehicles with engine capacities of 2.0 liters and above. There is no indication whether the move is in retaliation for the US actions. The latest round of trade disputes comes one week before US President Barack Obama is set to make his first official visit to Beijing.