Japan has raised concerns after confirming this week that two Chinese aircraft carriers operated together in the Pacific for the first time — a significant expansion of Beijing’s military presence beyond its usual reach. The development comes amid growing tensions over China’s assertive naval activities near disputed territories, and as Tokyo accelerates its own military preparations in response. According to Japan’s Defense Ministry, the Liaoning and the Shandong were spotted conducting nearly simultaneous operations near Iwo Jima, roughly 1,200 kilometre south of Tokyo. Defense Minister Gen Nakatani said the Liaoning also entered Japan’s exclusive economic zone near Minamitorishima, though it did not breach territorial waters. Both carriers launched and landed fighter jets during the exercises. On Saturday, a J-15 jet from the Shandong approached a Japanese P-3C reconnaissance plane within 45 metre, a maneuver which Tokyo described as “abnormally close.” A similar incident occurred Sunday. Japan lodged a formal protest, urging Beijing to prevent such high-risk encounters. Chief Cabinet Secretary Yoshimasa Hayashi said on Thursday Japan would maintain communications with China and step up its surveillance capabilities. Beijing's expanding reach worries Tokyo China’s growing naval footprint is a cause of mounting concern for Japan. Traditionally active within the so-called first island chain — stretching from Japan to Taiwan and the Philippines — China is now extending its reach to the second island chain, which includes US territory Guam. “China apparently aims to elevate its capability of the two aircraft carriers, and to advance its operational capability of the distant sea and airspace,” Nakatani said. Japan, in turn, is boosting its own defense posture, including deploying long-range cruise missiles and enhancing counter-strike capabilities. China says carrier exercises are routine China’s navy confirmed the dual-carrier deployment on Tuesday, calling it routine training in accordance with international law and not targeted at any country. The exercises are part of a broader effort to develop a “blue-water” naval force capable of long-distance, sustained operations, the Chinese naval force said. Despite having the largest navy in the world by number of vessels, China still trails the US significantly in aircraft carriers — three versus eleven. One of the US carriers, the USS George Washington, is permanently deployed in Japan. The Pentagon has previously warned that China’s aircraft carriers extend the range of its air defense and power projection capabilities far from its shores. Aircraft carrier capabilities The Liaoning, China’s first aircraft carrier, is a refitted Soviet ship, while the Shandong is a domestically built version based on the same design. Both use a “ski-jump” launch system for aircraft. China’s third carrier, the Fujian, launched in 2022, is undergoing final sea trials and is expected to be operational later this year. Unlike its predecessors, it features an advanced electromagnetic catapult system similar to US carriers. However, all three remain conventionally powered — unlike America’s nuclear-powered fleet, which offers greater range and endurance. Japan has cited repeated incidents involving Chinese vessels and aircraft in its surrounding waters. In August, a Chinese surveillance plane violated Japanese airspace over Nagasaki, while a Chinese research ship intruded into Japanese waters off Kagoshima. In September, the Liaoning and two Chinese destroyers passed between Japan’s westernmost island and Taiwan, skirting Japan’s controlled maritime zone. Tokyo is also wary of increasing Chinese military cooperation with Russia, including joint naval and air patrols near northern and southwestern Japan. (With inputs from AP)