China�s air force says it has held another round of drills in the South China Sea and the Western Pacific in preparation for possible future wars. 

"Air Force exercises are rehearsals for future wars and are the most direct preparation for combat," it said in a statement on Sunday.

The drill came after a US Navy destroyer on Friday sailed within 12 nautical miles of an artificial island China has built in the South China Sea, provoking condemnation from Beijing, which claims most of the strategic waterway.

Beijing said two Chinese ships “warned off” the vessel and blasted the move as “serious provocation,” stating that such military activities posed a challenge to China’s “sovereignty and security.”

US destroyer sails near Chinese island amid tensions

A US Navy destroyer has carried out a "freedom of navigation" operation, sailing close to the disputed South China Sea island controlled by China.

The air force said its aircraft, including H-6K bombers and Su-30 and Su-35 fighters, carried out combat patrols over the South China Sea and exercises in the Western Pacific.

The flights aim to help increase the air force�s ability to fight far out at sea, the statement said. 

The more exercises China practices far from its shores the better it will be positioned as "an important force for managing and controlling crises, containing war and winning battles," it added.

Last month, the top US admiral in the Asia-Pacific told Congress that America must prepare for the possibility of war with China which has shown a "crystal clear" intent to dominate the South China Sea.

US must �prepare� for war with China: Admiral

The top US admiral in the Pacific has told Congress that America must prepare for the possibility of war with China.

Earlier that month, the Trump administration proposed a military budget of $716 billion for fiscal 2019, part of an ambitious effort to substantially boost Pentagon spending after citing threats from Russia, China and North Korea.

Beijing sees American military presence in regional waters — far from US territory — as a potential security threat. China is wary of US military buildup in the region as well as Washington�s ties with Taiwan which Beijing regards as a part of Chinese territory. 

China is in the midst of a military modernization program overseen by President Xi Jinping with a heavy focus on its air force and navy, from building stealth fighters to adding aircraft carriers.

The country is set to increase its defense budget by 8.1 percent to 1.1 trillion yuan ($173 billion) in 2018, in an effort to further modernize the world’s largest army.