A nuclear-powered US aircraft carrier and accompanying battle group steamed into Malaysia on Wednesday for a rare visit described by the commanding officer as demonstrating Washington's commitment to security in the region.

"I hope this will be the first of many visits. This is an opportunity really to stand by a loyal and faithful partner and friend. It is also a demonstration of our commitment," Rear Admiral Patrick Walsh told reporters.

"Malaysia has been a good friend of the US and we want to reciprocate."

The carrier USS John C Stennis with 6,000 military personnel aboard and its battle group of five warships and a submarine were in Canada and Japan before arriving in Malaysia for a four-day visit through the narrow Malacca Straits.

The San Diego-based group last visited Malaysia in February 2000.

Walsh said the port call in Malaysia was by invitation of the Malaysian government, adding that it would enable the crew to "rest and relax and enjoy Malaysian culture."

Asked if the US and Malaysia would hold any exercises, he said there may be limited air exercises.

"We do have concerns about security and stability in the region and that is why we are here," Walsh said.

Security concerns

Anything that threatened the economies of the region was a concern to the US because "the world relies on the vibrant economies of Southeast Asia".

The visit comes in the wake of a dispute over reports that Washington wanted US forces to help patrol the Malacca Straits, off Malaysia's west coast, against possible terrorist attacks on shipping.

Malaysia rejected the idea of US involvement in the vital shipping lane, which carries a quarter of world trade and half its oil supplies, saying it would infringe on its sovereignty and attract rather than repel terrorism.

The commander of US forces in the Pacific, Admiral Thomas Fargo, visited Malaysia in June to deny the reports, saying cooperation would focus on intelligence-sharing and helping to build the capacity of countries in the region to face the threat themselves.

Walsh said the US recognised that countries bordering the straits - Malaysia, Indonesia and Singapore - are in the best position to enforce security.

"We can help build capacity. We can help with information and intelligence-sharing," he said.

Last month a fleet of five US navy ships conducted joint exercises in the South China Sea with the Malaysian navy.

The four-day annual Cooperation Afloat Readiness and Training exercises are aimed at bolstering military ties with several Southeast Asian nations and designed to enhance the ability of the US navy and its allies in the region to operate together.