Taiwan today sent the clearest message to China that it is taking deteriorating diplomatic relations with its estranged mainland cousin seriously, when the island nation began two days of military drills simulating an attack by China, in the wake of Beijing's sailing of an aircraft carrier through the Taiwan Strait, as the government sought to reassure the public.

The island's armed forces gathered in central Taiwan for annual drills that saw troops practise combat skills with tanks, attack helicopters and artillery. The drill was conducted in Taichung by the 10th Army Command and the Army Aviation and Special Forces Command. It simulated a scenario in which a Chinese naval fleet comprising destroyers, corvettes and amphibious assault ships was conducting training off China's southeastern coast.

In the scenario, first reported by Taiwan's China Post, the fleet unexpectedly sailed east across the hypothetical mid-line of the Taiwan Strait, and several helicopters also took off from the amphibious assault ships toward Taiwan's air defense identification zone. In counteraction, the Army dispatched M109 self-propelled howitzers, M60A3 main battle tanks, CM-32 armoured vehicles, AH-1 Cobra attack helicopters, and OH-58D Kiowa armed reconnaissance helicopters to launch an attack upon the enemy forces, in collaboration with paratroopers descending from UH-60L Black Hawk helicopters.

"The military has active measures to deal with the situation in the Taiwan Strait and the South China Sea so the public can rest assured. We will enhance training 365 days a year," defence spokesman Chen Chung-chi said.

Soldiers held positions next to a US-made Avenger air defence missile system during the drill in central Taichung city as special forces moved in formation through woods and a tank set off smoke bombs and crushed a car.

The Taiwan drill is likely in response to a recent show of force by Beijing when China sailed its only aircraft carrier through the strait last week. The Liaoning did not enter Taiwanese waters but went into an area covered by its air defence zone. Chinese military aircraft also passed near Taiwan on December 10 for the second time in less than a month.

In addition to the drills, the air force confirmed Tuesday an upgrade of Taiwan's 143 F-16s was under way, with materials supplied by US aerospace company Lockheed Martin which manufactured the jets. "Taiwan is the first country in the world to upgrade the F-16 A/B fighters to F-16 V. We are enhancing our aerial capabilities to ensure national security," an air force official told AFP.

The government-funded project, codenamed "Phoenix Rising" has a budget of Tw$110 billion ($3.47 billion) and aims to be complete within the next six years. Defence minister Feng Shih-kuan has said the F-16 V could match China's Chengdu J-20 stealth fighter, although Chinese media have dismissed this as an "illusion." The jets will be equipped with radar to detect stealth aircraft, as well as more advanced avionics and missiles, according to local media.

Minister Feng recently warned of growing threats from China and called for increased vigilance, urging the island's youth to join the military.

China has yet to file an official response, which will most likely come in its nationalistic, state-owned, Global Times tabloid.