Uninvited guest: A Chinese Song-class submarine surfaced near the USS Kitty Hawk

American military leaders were left dumbstruck by a Chinese submarine undetected popping up at the heart of a recent exercise in the Pacific and close to the USS Kitty Hawk a 1000ft supercarrier with 4500 people on board.

By the time it surfaced, the 160ft Song class diesel submarine attack is understood to have sailed within range viable for launching torpedoes or missiles on the carrier.

According to senior officials of NATO incident has caused consternation in the United States Navy.

The Americans had no idea of the fast-growing China submarine fleet had reached such a level of sophistication, or that it poses such a threat.

A NATO official said the effect was "a shock as big as the launch of Sputnik Russians" - a reference to the Soviet Union's first satellite into orbit in 1957, which marked the beginning of the space age.

The incident, which took place in Southern Ocean between Japan and Taiwan, is a major embarrassment for the Pentagon.

The only Chinese ship slipped past at least a dozen other U.S. warships that are supposed to protect the carrier from enemy aircraft or submarines and the rest of the defensive expensive screen, which includes at least two American submarines, was also apparently unable to detect it.

According to the NATO source, the meeting has forced a major rethink by American and NATO commanders to reconsider the level of threat potentially hostile submarines Chinese.

It also led to tense diplomatic exchanges with shaken American diplomats demanding to know why the submarine was infiltrating while the American fleet is conducting exercise. Beijing pleaded ignorance and dismissed the case as a coincidence.

Analysts believe Beijing was sending a message to America and the West showing off the ability to threaten military foreign powers try to interfere in its "backyard".

The People's Liberation Army Navy submarine fleet includes at least two nuclear missiles launching boats.

The current 13 boats of Song Class submarines are very quiet and difficult to detect when running on electric motors.
Commodore Stephen Saunders, editor of Jane's Fighting Ships, and a former Royal Navy specialist in anti-submarine warfare, said the United States had paid relatively little attention to this form of warfare since the end of the cold war. He said: "It was certainly a wake-up call for Americans.

"It would tie in with what we see the Chinese are trying to do, what appears to be to dissuade the Americans from holding or interfering in their backyard, especially in relation to Taiwan."

In January China conducted a successful test missile to shoot down a satellite in orbit for the first time.