It is our prerogative and right to fly over international airspace to preserve the peace by flying reconnaissance missions

White House spokesman Ari Fleischer

The plane's presence drew no response from the Chinese military and was not intercepted by their fighter planes, added US official.

Last month's mid-air collision, which resulted in the death of the Chinese pilot, sparked a serious diplomatic dispute between the two countries, and it was 11 days before the crew of the US spy plane was allowed to return home.

Beijing demanded an end to US surveillance flights off its coast.

White House spokesman Ari Fleischer declined to confirm the resumption of surveillance flights, adding that the US has always said it is its "prerogative and right to fly over international airspace to preserve the peace by flying reconnaissance missions".

Washington had earlier hinted future surveillance flights might be escorted by US fighter jets. However, Monday's mission was completed without an escort.

US inspection

The resumption of flights follows the inspection by US technicians of the American EP-3 aircraft which has been held by the Chinese on Hainan Island since it was forced to make an emergency landing there after last month's collision.

Rumsfeld: Confident China will return the plane

The technicians reported that the plane could be repaired sufficiently to fly it out of Chinese territory. Another alternative would be to dismantle it and ship it out by boat.

On Sunday, US Defence Secretary Donald Rumsfeld said he believed Beijing would release the $80m aircraft.

"I would suspect we'll get it back. They wouldn't have allowed an inspection team to go in there if they didn't plan to return the airplane."

The RC-135 spy plane

Equipped to collect electronic signals Crew: 21-27, depending on mission First deployed in the 1960s, has been extensively modified Used for operations in Vietnam, Grenada, Panama, the Gulf and the Balkans The US air force has 14 of these planes in locations around the world

US officials say the Chinese are likely to have gained valuable intelligence during the weeks they did not allow Americans to inspect it.

But the US spy plane is not the only issue straining Sino-American relations at the moment.

There was further confusion last week as the Pentagon made public an order suspending all military contacts with China. The statement was retracted two hours later and attributed to a misinterpretation of Mr Rumsfeld's intentions.

The Bush administration now says it is reviewing contacts and activities with the Chinese armed forces on a case-by-case basis.

Beijing, for its part, blasted President George Bush's plans for a US missile defence system, describing them as "supremacist", and warned it could "break the present fragile global security equilibrium".