A major multinational naval exercise led by the U.S. Navy has been launched in the Pacific with 25 other nations participating amid growing U.S.-China tensions.

U.S. allies in the Indo-Pacific region including Japan, South Korea, Australia, New Zealand and the Philippines are participating in the biennial Rim of the Pacific exercise, regarded as the world's biggest naval training starting from Wednesday, according to the U.S. Navy.

The exercise, known as RIMPAC, started at a time China is maintaining military pressure on Taiwan. Beijing views the self-ruled democratic island as part of its territory to be reunified and is asserting its territorial claims more aggressively in the East and South China seas.