HONG KONG — China is holding military drills around Taiwan simulating the seizure and blockade of the island's key areas, as a warning against "separatist forces".

Codenamed "Justice Mission 2025", the drills are taking place days after the US announced the sale of one of its largest weapons packages to Taiwan worth $11bn (£8.2bn). That move drew sharp protest from Beijing which in turn sanctioned US defense firms.

China’s military announced Monday it was mobilizing army, navy, air and rocket units around Taiwan for “major military drills” aimed at sending a “serious warning” against any push for Taiwanese independence and “external” forcing interfering with the island.

The exercises would test combat readiness and “blockade and control of key ports and critical areas,” China’s Eastern Theater Command said. Live-fire activities would take place in five maritime and airspace zones encircling the island, according to information released by the command.

Taiwan’s government condemned the drills, accusing China of “military intimidation,” while its defense ministry said it was “fully on guard” and would “take concrete action to defend the values of democracy and freedom.”

Beijing has been ramping up its military intimidation of the island in recent years, including launching major drills at sensitive moments to express its displeasure – a playbook the latest exercises appear to follow.

China and Japan have been locked in a weeks-long diplomatic spat over comments the Japanese prime minister made about Taiwan. Washington and Taipei also earlier this month announced what could become one of the US’ biggest-ever military sales to the island.

Meanwhile Taiwan’s president is pushing for the approval of a historic special defense budget – all of which has irked Beijing.

China’s ruling Communist Party claims the self-governing democracy of Taiwan as its own territory, despite never having controlled it, and has vowed to take control of the island, by force if necessary.

“This exercise serves as a serious warning to ‘Taiwan independence’ separatist forces and external interfering forces,” Shi Yi spokesperson for the Eastern Theater Command said, using what appeared to be a veiled reference to the US and its allies. “(It) is a legitimate and necessary action to safeguard national sovereignty and maintain national unity.”

Other voices cited in Chinese state media were more explicit. In an interview published on a social CCTV, military analyst Fu Nan pointed to the US and Taiwan arms deal when asked why the drills were taking place at this time, calling it an “escalation” of “collusive actions.”

In a statement, Taiwan’s presidential spokesperson Karen Kuo said the drills “blatantly undermine the security and stability status quo of the Taiwan Strait and the Indo-Pacific region” and “openly challenges international laws and order.”

The landmark $11.1 billion arms deal between US and Taiwan includes HIMARS rocket systems, anti-tank and anti-armor missiles, loitering drones, howitzers and military software.

Washington recognizes the People’s Republic of China as the sole legitimate government of China; it also acknowledges Beijing’s position that Taiwan is part of China, but has never accepted the Chinese Communist Party’s claim of sovereignty over the island.

The US maintains close unofficial ties with Taiwan, which have been strengthened in recent years. It is bound by law to provide the island with the means to defend itself, and supplies it with defensive weaponry.

The announcement of the latest military drills has been accompanied by the usual release of nationalistic propaganda geared toward China’s domestic audience, including a poster showing fiery arrows reigning down on the island captioned “Arrow of Justice, Control and Denial.”

It’s was not immediately clear how long the war games would last. Shi said naval and air forces would run combat readiness patrols from December 29 and the command released a notice announcing the closure of maritime and airspace zones around Taiwan for live-fire drills on December 30 daytime.

China Coast Guard also announced Monday it was starting law enforcement patrols in waters near Taiwan and two of its outlying islands.

China’s drills come at a moment of heightened focus on Taiwan both in Beijing’s diplomatic and domestic discourse in large part due to its frictions with Japan.

Beijing has unleashed its ire on its regional neighbor after Japanese Prime Minister Sanae Takaichi suggested her country could respond militarily if China were to move to take control of Taiwan by force – comments Beijing sees as a direct threat against its sovereignty.

Taiwan is also seen by Beijing as the principle “red line” in US-China relations, with Chinese officials long condemning the unofficial relationship between Taipei and Washington.

Beijing slammed the recent arms deal announced between the two, saying the move “infringes on China’s sovereignty, security and territorial integrity, undermines peace and stability in the Taiwan Strait.”

Taiwan has been ramping up military purchases in recent years as it comes under increasing pressure from Beijing, with Chinese aircraft and ships present almost daily around Taiwan as well as regular large-scale exercises in and over the surrounding waters.

Parts of latest deal, however, are expected to be paid for as part of an historic $40 billion special defense budget Taiwan’s President Lai Ching-te proposed in late November, which has struggled to gain approval in Taiwan’s opposition-controlled legislature. — Agencies