China test-fired an intercontinental ballistic missile (ICBM) into the Pacific Ocean this week in a rare occurrence, further adding to tensions in the region where multiple countries have overlapping territorial claims and both Beijing and Washington seek to project their influence.

The launch was part of routine training by the People's Liberation Army Rocket Force, which is in charge of conventional and nuclear missile operations, and was not aimed at any country or target, the defence ministry said in a statement.

The ICBM, carrying a dummy warhead, landed in a designated area in the sea, the ministry said, without specifying where exactly.

China rarely tests ICBMs out in international waters, with some experts tracing the last such deployment back to May 1980, when Beijing launched a DF-5 missile into the South Pacific. 

Usually, the army test-fires ballistic missiles in China's remote Xinjiang region or the Bohai Sea.

Why the Pacific, why now?

China choosing the Pacific Ocean as the location for test-firing its missile comes across as both a display of its increased nuclear capabilities and as a warning to the United States and its allies in the region, experts say.

"There is no other potential audience, as China does not expect to have to confront the EU or the UK militarily," said SOAS China Institute director Steve Tsang. 

The test also comes weeks ahead of an expected call between Chinese leader Xi Jinping and US President Joe Biden. 

It marks an increase in regional security tensions with US allies Japan and the Philippines, and a continuation of frictions with the self-ruled island of Taiwan, which Beijing claims as its territory.

On Wednesday, local time, Taiwan's defence ministry said it was monitoring the missile launch, along with other military exercises by China in the region.

The launch, coinciding with the United Nations General Assembly meeting in New York, "is a pretty blunt signal" to the international order, said senior fellow at the S. Rajaratnam School of International Studies in Singapore, Drew Thompson. 

"China is signalling that its forbearance has limits, that it is prepared to use its most powerful weapons to deter adversaries or punish them if needed, if deterrence fails," the former US defence official said. 

Wednesday's launch also follows a series of corruption arrests this year that ensnared several leading officers in its rocket corps on allegations of misconduct. 

Its aim could be to both provide assurances at home and signal to the world that the issues have been resolved.

How strong is China's military?

China boasts the world's largest standing army and the biggest navy. 

Its military budget is the second highest in the world, after that of the US.

According to the US, China also has the largest air force in the Indo-Pacific, with more than half of its fighter planes consisting of fourth- or fifth-generation models. 

China also boasts a massive stockpile of missiles, along with stealth aircraft, bombers capable of delivering nuclear weapons, advanced surface ships and nuclear-powered submarines.

In his more than a decade in power, Mr Xi, who is also chairman of the Central Military Commission, has spearheaded the armed forces' modernisation, with investments in high-tech military technologies from stealth fighters to aircraft carriers and a growing arsenal of nuclear weapons.

China's defence budget has more than doubled since 2015, even as the country's economic growth rate has slowed considerably. 

A US Department of Defense report last year said China has continued to strengthen the army's ability to "fight and win wars against a strong enemy".

How do China's missiles compare to those of other countries?

The US report also estimated China had more than 500 operational nuclear warheads as of May 2023 and was on track to accumulate more than 1,000 operational nuclear warheads by 2030.

China has not revealed the size of its nuclear arsenal.

In comparison, Russia is believed to have a total inventory of more than 5,580 warheads — including 4,380 stockpiled warheads for operational forces, as well as an additional 1,200 retired warheads awaiting dismantlement — according to a report this year by the Federation of American Scientists.

The same report put the US nuclear warheads at 5,044.

How common are missile tests in the region?

Few countries have ICBMs in their arsenal, and testing is usually restricted to their own territory. 

North Korea has carried out multiple ICBM tests since 2017, including firing a developmental solid-fuelled missile in December that came down in the waters between the Korean Peninsula and Japan.

The US earlier this year launched two unarmed ICBMs equipped with re-entry vehicles from California and brought them down on an American test site in the Marshall Islands.

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