China has for the first time confirmed it is building a third aircraft carrier — a move that came ahead of an announcement by Tokyo that is considering transforming one of its helicopter destroyers into an aircraft carrier that can accommodate fighter jets.

In an article published Sunday to mark the sixth anniversary of the inaugural takeoff and landing of a Chinese fighter jet on the country’s first carrier, the official Xinhua News Agency said that the nation’s second domestically designed carrier had undergone sea trials and that a “new-generation carrier” is being constructed at a shipyard.

The report did not elaborate on the progress of the latest carrier, but it was the first official confirmation.

“Six years have passed, our domestic carrier has been trialed, entry into service is just around the corner. The new aircraft carrier has also been built on the slipway,” the article said.

China’s second aircraft carrier, known as the Type 001A, was the country’s first domestically built vessel of its type — the first, the Liaoning, was a refurbished Soviet vessel. The Type 001A has been conducting sea trials this year.

But rumors had swirled in recent months that another, more advanced vessel, was already under construction in China. In June, a top Chinese ship design firm, the No.701 Research Institute of China Shipbuilding Industry Corp., stoked speculation when it released a mock-up photo of an unidentified aircraft carrier with its two other carriers.

State-run media said the new vessel could have an electromagnetic catapult aircraft launch system, technology similar to systems employed by the U.S. Navy’s newest and most advanced type of aircraft carrier.

Both the Liaoning and the Type 001A use an older launching system known as the ski-jump, which relies on a plane’s own power to take off.

Wang Yunfei, a naval expert and retired Chinese Navy officer, told the state-run Global Times tabloid on Monday that the new aircraft carrier might need about 2½ years to be launched because of its bigger size, noting that the construction of the Type 001A took less time because it was based on the Liaoning. But the third carrier, Wang said, would employ cutting-edge technologies and would not be based on an earlier vessel.

On Tuesday, a Japanese government source said the country was weighing the remodeling of the Maritime Self-Defense Force’s helicopter carrier Izumo — in what could be seen as a departure from the country’s strictly defense-oriented policy under its pacifist Constitution.

Proponents say the move is necessary if the country is to beef up its defense capabilities in the face of China’s growing maritime assertiveness in the waters around the disputed Senkaku Islands in the East China Sea.

Media reports quoting government sources said it plans to state its policy of renovating a destroyer so it can carry fighter jets in defense buildup guidelines set to be updated next month.

Currently, the MSDF’s 19,500-ton Izumo is 248-meters long and can carry up to 14 helicopters.

Under the war-renouncing Article 9 of the Constitution, Japan has maintained that it cannot possess attack aircraft carriers as it is only allowed to use force for self-defense.