BEIJING, Feb. 14 (Xinhua) -- China on Thursday rejected the U.S. allegations of espionage, saying the charges were "groundless" and "with ulterior motives."

    "The so-called accusation against China on the issue of espionage is totally groundless and has ulterior motives," Chinese Foreign Ministry spokesman Liu Jianchao told a regular press briefing.

    "We urged the United States to abandon its Cold War thinking and stop groundless accusations and instead contribute to increasing mutual trust and friendship between our two peoples," Liu said.

    "For a period of time, certain country has made irresponsible fabrication on this issue and staged some farces," he said, adding "I think everyone is now tired of these farces which should come to an end."

    The U.S. Justice Department said Monday that four people were arrested in the United States on charges of spying for China in two separate cases.