Naval ships from 22 nations on Friday kicked off the biennial Rim of the Pacific (RIMPAC) exercise, billed the largest international maritime drill, in and around the Hawaiian Islands.

Scheduled June 29 to Aug. 3, the drill was participated by 42 ships, six submarines, more than 200 aircraft and 25,000 personnel from countries including Russia, New Zealand and Singapore.

According to the US military, RIMPAC provides a "unique training opportunity that helps participants foster and sustain the cooperative relationships that are critical to ensuring the safety of sea lanes and security on the world's oceans." RIMPAC 2012 is the 23rd exercise in the series that began in 1971.

The drill was hosted by US Pacific Fleet, and led by Vice Adm. Gerald Beaman, commander of the US Third Fleet. It also marks the first time non-US officers will command components of the combined task force during the exercise. Commodore Stuart Mayer of the Royal Australian Navy will command the Maritime Component and Brig. Gen. Michael Hood of the Royal Canadian Air Force will command the Air Component.

Participating nations and forces will exercise a wide range of capabilities and demonstrate the inherent flexibility of maritime forces, according to the US military. These capabilities range from disaster relief and maritime security operations to sea control and complex warfighting. The relevant, realistic training syllabus includes amphibious operations; gunnery, missile, anti- submarine and air defense exercises as well as counter-piracy, mine clearance operations, explosive ordnance disposal and diving and salvage operations.

US has made it clear it is to shift security priority to the Asia Pacific, and fostering partnership in the age of defense cuts is a major component in its strategy.