China Defense Minister Says Nuclear Buildup Is Justified

U.S. Defense Secretary Lloyd Austin said Saturday that China was taking a more aggressive approach to territorial claims and that its military was increasingly engaging in provocative behavior, including around Taiwan, where Chinese warplanes have been probing the island’s air defenses.

On Sunday, Gen. Wei responded, saying it was U.S. strategy in the Asia-Pacific region that was propelling the two sides toward confrontation. On Taiwan, he issued a defiant message often voiced by Beijing. “No one should ever underestimate the resolve and ability of the Chinese military to safeguard its territorial integrity,” he said.

Gen. Wei and Mr. Austin had their first face-to-face meeting last week ahead of the Shangri-la Dialogue, a gathering of high-level military officers and defense officials that has often provided an opportunity for contacts between the American and Chinese sides.

This year’s discussions came amid elevated tensions over Taiwan and a war in Europe that have both highlighted military divisions between the U.S. and China. They followed remarks by President Biden during a visit to Tokyo in May saying the U.S. would respond militarily to any Chinese effort to take Taiwan by force.

In Gen. Wei’s speech Sunday, he said U.S. moves in the region—including its alliance with Australia, Japan and India, informally known as the Quad—could create conflicts by encouraging Asian countries to target China. He also addressed Beijing’s stance on Russia’s invasion of Ukraine—another point of tension with the U.S.—by repeating previous assurances that China isn’t providing Russia with any weapons.

Gen. Wei also spoke about China’s nuclear arsenal, saying it was purely for defensive purposes and reiterating Beijing’s pledge never to strike first with such weapons.

“China is developing nuclear capabilities at a moderate and appropriate level,” Gen. Wei said. “That means being able to protect our nation’s security so that we can avoid the catastrophe of a war, especially the catastrophe of a nuclear war.”

While Gen. Wei didn’t characterize the size of expansion of the nuclear arsenal while responding to a question about the weapons after his formal speech, it was a rare public comment by a top Chinese military official about a program that the U.S. says is growing and should be subject to arms-control talks.

Gen. Wei, who previously commanded China’s missile force, said the country’s military modernization has included the deployment of all new weapons displayed in a 2019 military parade in Beijing. Among those featured in the parade were the Dongfeng-41 intercontinental ballistic missile, which can carry multiple nuclear warheads and has the range to hit the continental U.S.

Gen. Wei stopped short of linking the issue of nuclear weapons and Beijing’s stand toward Taiwan, but he reiterated China’s long-held positions that it intends to control the self-governed island and will forcefully oppose efforts to promote its independence from mainland China.

Beijing’s nuclear-weapons program has trailed far behind those of the U.S. and Russia for decades. In recent years, China has begun to rapidly expand its nuclear arsenal, according to U.S. intelligence estimates. People familiar with the Chinese leadership’s thinking say the buildup is driven by an assessment that the U.S. may be more willing to challenge it militarily, including in a possible clash over Taiwan.

China has declined to provide any clarity on its nuclear program and has rejected U.S. moves to start arms-control talks. Japanese Prime Minister

Fumio Kishida

criticized Beijing’s nuclear secrecy at the conference on Friday and said it should engage in talks with Washington.

The Pentagon forecasts China may have around 1,000 nuclear warheads by the end of this decade, compared with a few hundred now. The U.S. and Russia each have around 4,000 nuclear warheads.

Beijing has also developed and deployed more missiles that can carry nuclear warheads. Satellite images suggest construction has accelerated this year on more than 100 suspected missile silos in China’s remote western region that could house Dongfeng-41 missiles.

At the Singapore conference, Gen. Wei didn’t answer a question about the suspected silos, but he reaffirmed Beijing’s stance that it wouldn’t initiate a nuclear conflict. Some U.S. officials and analysts doubt those reassurances.

Tensions between Washington and Beijing over the issue of Taiwan flared in May when Mr. Biden said that the American military would respond militarily to defend Taiwan if China invaded, the third time he has made such a statement. U.S. administrations have long maintained a policy of not stating whether its military would help to defend Taiwan from attack, while selling the island weapons to defend itself. Mr. Biden later said the U.S. position was unchanged.

An increase in Chinese military flights near Taiwan this year has elevated concerns among Taiwanese and American government officials of Beijing’s intentions. China has also held military exercises simulating an amphibious assault that military experts say would likely be part of any invasion. China says the self-ruled island is part of its territory and hasn’t ruled out the use of force to bring it under its control.

In a meeting on Friday that was dominated by the issue of Taiwan, Mr. Austin told Gen. Wei that U.S. policy toward the island hadn’t changed, according to the U.S. side. The Chinese defense minister said Beijing’s military would fight to prevent any move for independence by the island, according to a spokesman, but both sides gave accounts of the meeting that suggested a cooling off of friction, and each side emphasized the need to keep open lines of communication to head off crises.

Write to Keith Zhai at keith.zhai@wsj.com and Alastair Gale at alastair.gale@wsj.com