China has started live-fire military exercises around Taiwan, hours after announcing "major" drills in waters and airspace near the self-governed democratic island.
China's military "is employing destroyers, frigates, fighters, bombers and unmanned aerial vehicles" in the drills that include "live-fire training on maritime targets to the north and southwest of Taiwan", a statement by the People's Liberation Army said.
Taiwan authorities said it had detected four Chinese coastguard ships near the democratic island's waters, as China announced the start of live-fire drills.
The four vessels were "sailing near waters off Taiwan's northern and eastern coasts today", the Taiwanese coastguard said, adding it "immediately deployed large vessels to pre-position responses in relevant areas" and "sent additional support units".
Earlier China announced "major" military exercises around Taiwan saying it would conduct live-fire drills the following day across five zones in waters and airspace near the island.
China claims self-governed Taiwan as part of its sovereign territory and has refused to rule out using military action to seize the island democracy.
The latest show of force follows a bumper round of arms sales to Taiwan by the United States, Taiwan's main security backer.
China will send army, navy, air force and rocket force troops to conduct "major military drills" code-named "Justice Mission 2025", said Senior Colonel Shi Yi, spokesman for the People's Liberation Army's Eastern Theater Command.
The drills are "a stern warning against 'Taiwan Independence' separatist forces, and... a legitimate and necessary action to safeguard China's sovereignty and national unity", Mr Shi said.
Plans involve vessels "approaching the Taiwan Island in close proximity from different directions", he said.
The "joint assaults" are intended to "test their joint operations capabilities", he added.
The activities will focus on "sea-air combat readiness patrol, joint seizure of comprehensive superiority, blockade on key ports and areas, as well as all-dimensional deterrence outside the island chain", Mr Shi said.
Taiwan condemned China's "disregard for international norms and the use of military intimidation to threaten neighbouring countries", Presidential Office spokeswoman Karen Kuo said.
Taiwan's military said it had established a response centre, deployed "appropriate forces" and "carried out a rapid response exercise".
The drills by China's ruling Communist Party "further confirm its nature as an aggressor, making it the greatest destroyer of peace", Taipei's defence ministry said.
China's military last held large-scale drills involving live firing around Taiwan in April.
The United States called them "intimidation tactics", and Britain warned they were "risking dangerous escalation".
China said this month it would take "resolute and forceful measures" to safeguard its territory after Taiwan said the US had approved a major $11 billion arms sale.
China announced fresh sanctions on 20 American defence companies last week, though they appeared to have little or no business in China.
Last month, Japan's Prime Minister Sanae Takaichi triggered a backlash from China when she said the use of force against Taiwan could warrant a military response from Tokyo.
China demanded that she retract her statement, summoned Tokyo's ambassador, and warned its citizens against travelling to Japan.
China warns 'external forces' over Taiwan support
China made a warning against "external forces" backing Taiwan after the drills.
Foreign ministry spokesman Lin Jian told a regular news conference that any attempts to stop China's unification of Taiwan with the mainland would fail.
This week's show of force follows a bumper round of arms sales to Taipei by the United States, Taiwan's main security backer.
