Former Massachusetts Governor Mitt Romney, a leading candidate for the Republican presidential nomination, has criticized Obama for not taking a stronger stand on China, specifically over Beijing's efforts to manipulate its currency. Romney has said that, if elected, he would label China a currency manipulator on his first day in office, a move that could lead to trade sanctions against China.Under the terms of the WTO complaint, China has 10 days to respond and must hold talks with the U.S., E.U. and Japan within 60 days. If an agreement cannot be reached within that time frame, the U.S. and its partners could request a formal WTO panel to investigate Chinese practices. ___ Associated Press writer Tom Raum contributed to this report.