Mr Gates has voiced concerns over Beijing’s latest high-tech weaponry US Defence Secretary Robert Gates has aired concerns about China’s rapidly developing military capabilities, as he flew into China on a four-day trip.
Mr Gates is to meet President Hu Jintao and other top officials, at a time of strained military relations.
The visit comes days after websites published pictures apparently showing a working prototype of a Chinese stealth aircraft, invisible to radar.
China has not officially commented on the photos.
But they have once again put the spotlight on China’s military modernisation, after the US said China was still years away from deploying a stealth aircraft.
Photos of a possible working prototype of a Chinese-made stealth aircraft were recently leaked The US has the world’s only operational stealth fighter, the Lockheed Martin F-22 Raptor.
“[The Chinese] clearly have potential to put some of our capabilities at risk,” Mr Gates said ahead of his arrival in Beijing. “We have to pay attention to them, we have to respond appropriately with our own programmes.”
The US has been watching closely as China increases its military capacity – in particular, its development of a so-called “carrier killer” missile, a land-based system which could sink an aircraft carrier from up to 1,800 miles (2,900km) away.
US battle groups – including aircraft carriers – are stationed in the South China Sea.
And in August, the Pentagon reported that China had been expanding its nuclear arsenal and submarine force, as well as upgrading its land-based missiles.
Japan last month defined China as its main military concern, citing Beijing’s increased assertiveness in the East and South China Seas.
Beijing insists its military modernisation poses a threat to no one.
China’s official military budget quadrupled between 1999 and 2009 as the country’s economy grew.
Last year, China announced a smaller-than-usual 7.5% increase to $76.3bn.
The US defence budget is still the biggest in the world at around $700bn, but China’s is the second largest and the rate of increase may well go up this year.
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