MANILA - Navies from the United States and the Philippines kicked off an 11-day joint exercise Tuesday afternoon in waters off the southwestern Philippine island province of Palawan, showcasing the ties and interoperability between the two allies.

Dubbed the 17th "Cooperation Afloat Readiness and Training" ( CARAT), the exercise was held in the Sulu Sea east of Palawan and is expected to wind up on July 8, both navies said.

Guided missile destroyers USS Chung-Hoon, USS Howard and the diving and salvage ship USNS Safeguard are the US Navy's centerpieces for the exercise, US navy said earlier in a statement, adding that in addition to the three ships, other participants include P-3C Orion aircraft, SH-60 Seahawk aircraft, US Navy Seabees, a US Coast Guard Maritime Safety and Security Team, US Navy Mobile Security Squadron, US Navy Riverine Forces and Medical Support personnel.

On the Philippine side, patrol ships BRP Pangasinan and BRP Rizal are dedicated for the exercise, according to Lt. Noel Cadigal, spokesman of the Philippines' Naval Forces West.

The at-sea phase of the exercise focuses on developing maritime security capabilities in areas such as maritime interdiction, information sharing, combined operations at sea, patrol operations, gunnery exercises, as well as anti-piracy and anti-smuggling exercises.

Ashore training includes such specialties as Visit, Board, Search and Seizure (VBSS) exercises; diver training; salvage operations; joint medical, dental and civic action projects, aircrew familiarization exchanges, etc.

"The main purpose of the activity is to strengthen the ties and cooperation between the two navies by the exchange of knowledge and skills in the field of navigation and naval operations, particularly maritime defense, port security, resource protection and disaster response," said Philippine Navy spokesman Lt. Col. Omar Tonsay, noting the exercise is among the bilateral trainings conducted under the auspices of the Mutual Defense Treaty, which was signed between the Philippines and the United States in 1951.

However, the exercise and the Mutual Defense Treaty were bombarded by a left-wing group in the Philippines.

In a statement issued prior to the exercise, New Patriotic Alliance, known as Bagong Alyansang Makabayan in Filipino, said the fact that the joint naval exercise will be between modern US warships and ageing Philippine patrol ships shows the entire concept of US military assistance is a failure.

"After 60 years of the Mutual Defense Treaty, several decades of US military bases and 12 years of the Visiting Forces Agreement, our AFP (Armed Forces of the Philippines) has not modernized. We were promised the same in exchange for approving all these one-sided agreements and yet here is our navy, still employing World War II- era ships," said Renato Reyes, Jr., secretary general of the New Patriotic Alliance.