Economist and New York University professor Nouriel Roubini says the United States and China are on a "collision course" over the Chinese currency and investors are underestimating the "consequences" for global financial markets.

“The risk of a collision course on China’s currency peg and a wider trade rift between the world’s largest debtor and creditor nations has risen significantly in recent months,” Roubini wrote in a note to clients.

“Markets do not seem to be pricing in the potential consequences of the U.S. labeling China a 'currency manipulator,' which could be significant even if both sides avoid taking immediate bilateral actions.”

Roubini sees a 50 percent chance that the U.S. government will label China a currency manipulator, which would make it easier for U.S. companies to seek import duties, Bloomberg reports.

The Treasury Department is “seriously considering” labeling China a currency manipulator in an April 15 report, Senator Charles Schumer has said.

China has kept the yuan at 6.83 per dollar since mid-2008 to shield exporters from the global recession and a contraction in world trade.

U.S. lawmakers taking aim at China's currency policy were given more ammunition by a study from the Economic Policy Institute that says the trade deficit with China cost more than 2.4 million U.S. jobs between 2001 and 2008, The Wall Street Journal reports.

"We've known for years that U.S. manufacturing was paying a heavy price for China's activities, but these figures exceeded even our worst expectations," Schumer told reporters on a conference call.