China said Thursday that US Defence Secretary Leon Panetta will visit in mid-September, the latest in a flurry of diplomatic activity between the two countries.

US Secretary of State Hillary Clinton is due to visit Beijing next week to discuss major issues concerning the world's two largest economies, including maritime disputes between China and its Asian neighbours.

Panetta's visit is part of planned military-to-military exchanges and follows a trip by China's Defence Minister Liang Guanglie to the United States in May, a spokesman for the defence ministry said.

Spokesman Geng Yansheng said China and the United States plan other military exchanges and joint exercises aimed at combating piracy, according to a transcript of a news conference posted on the ministry's website.

During Liang's trip, the first visit by a Chinese defence minister to Washington in nine years, the two countries announced plans for a joint counter-piracy naval exercise in the Gulf of Aden later this year.

But China has voiced worries over the US "pivot" towards Asia and state media has accused Washington of seeking "dominance and hegemony" in the Asia-Pacific region.

US guard pleads guilty to planning to spy for China
Washington (AFP) Aug 30, 2012 - A former civilian guard at a US consulate in China pleaded guilty Thursday to charges that he planned to sell secrets to Chinese security officials, the US Justice Department said.

Bryan Underwood, a 32-year-old American who worked at the US consulate in the southeastern Chinese city of Guangzhou, pleaded guilty to "attempting to communicate national defense information to a foreign government."

Underwood worked at the Guangzhou consulate from November 2009 to August 2011 as a "cleared American guard", a civilian with "Top Secret" clearance.

In March, 2011, Underwood "lost a substantial amount of money in the stock market," the statement said reported.

He told US law enforcement he had "devised a plan" to use his security clearances to sell information to China's Ministry of State Security for anywhere between $3 million and $5 million, according to the statement.

Underwood snuck a camera into the consulate in May and "took photographs of restricted building and its contents," the statement said.

It added that he took notes on security system upgrades and drew a diagram of surveillance camera locations at the consulate.

State Department officials reviewed the information and reported that the leak "could cause serious damage to the United States."

"Bryan Underwood was charged with protecting a new US Consulate compound against foreign espionage but, facing financial hardship, he attempted to betray his country for personal gain," US assistant attorney general for national security, Lisa Monaco, wrote in the release.

Washington has found no evidence that Underwood successfully passed information along to Chinese authorities.