WASHINGTON, Aug. 13 (SCMP) - The US Air Force has deployed three B-2 stealth bombers to the tiny island of Diego Garcia in the Indian Ocean for the first time since 2016, as China continues to ramp up its live-fire military exercises.

The American B-2A nuclear-capable Spirit bombers took off on Tuesday from the Whiteman air force base in Missouri, flew across northern Australia and on to the militarised atoll that forms part of the British Indian Ocean Territory. The aircraft were refuelled in the air several times, according to information from the US military.

The last time the bombers were deployed to Diego Garcia, which lies about 1,200km (745 miles) south of the Maldives, was four years ago during a period of tension in the South China Sea after an international arbitration tribunal rejected Beijing’s claims to the disputed waters.

While the three bombers, with the call signs Reaper 11, 12 and 13, did not pass over sensitive areas of the western Pacific, South China Sea or Taiwan Strait, their presence on Diego Garcia is a clear sign of the United States’ military strength in the Indo-Pacific, observers said.

“The movement of air-based nuclear power is a demonstration of might,” said Zhao Tong, a senior fellow at the nuclear policy programme at the Carnegie Endowment for International Peace in Beijing. “There doesn’t need to be a strike.”

Unlike submarines that are less visible, and land-based missiles, which are less mobile, strategic bombers, which can be deployed and withdrawn at will, are often used as a tool to intimidate an enemy.

The bat-shaped B-2 is the most advanced strategic bomber in the world, with stealth capabilities that can penetrate air defence systems.

“A stealth bomber is hard to detect or intercept,” said Beijing-based military commentator Zhou Chenming.

“So if it flew into the Chinese airspace with a nuclear warhead, it would be up to the Americans to decide if they wanted to start a war.”

The US bomber deployment comes amid a period of intense military manoeuvring by the People’s Liberation Army (PLA), as Beijing finds itself increasingly at odds with not only the US, but also Taiwan and India.

Chinese troops are set to begin two days of live-fire drills off the Zhoushan Islands – an archipelago about 550km north of Taiwan – on Monday.

The PLA has accused the United States of “continuously making negative moves that send the wrong messages” to independence forces in Taiwan, a self-ruled island that Beijing considers part of its sovereign territory.

“Our forces will be on high alert at all times and take all necessary measures to counter any attempt to split the country and make Taiwan independent,” a spokesman for the Eastern Theatre Command said on Thursday.

Zhou said that although China could do nothing about the US military deployments it might respond by boosting its counter-attacking capabilities.

“The change to the balance of power caused by the [US] deployment might cause a fresh crisis,” he said. “It doesn’t help to settle the problem, but worsens it.”