Tokyo's military is holding a ceremony later in the day in the port city of Yokohama to show off its new 248-metre helicopter carrier, which will be a centrepiece of its naval power.
The vessel was announced several years ago but the ceremony comes as the conservative government mulls boosting military capabilities with debate swirling over a possible overhaul of Tokyo's pacifist constitution.
The Japanese-built carrier can accommodate nine helicopters and is expected to play a major role in disaster and rescue missions, as well as defending sea lanes and Japanese territory, according to the defence ministry. It is unclear when it will go into service.
Less than two weeks ago, the Chinese coastguard entered waters disputed with Japan for the first time, upping the ante in a festering row over ownership of the Senkakus, which Beijing also claims and calls the Diaoyus.
More From This Section
The rocky islands are located in rich fishing grounds in the East China Sea and are believed to harbour vast natural resources below their seabed.
The incursion came as Japan's defence ministry recommended establishing amphibious units and acquiring surveillance drones, similar to the US Marines, to protect its claim on outlying islands.
Prime Minister Shinzo Abe has been mulling a beefed-up military, which would require changing the constitution imposed on Japan by the US and its allies following WWII.
A possible overhaul of the constitution has stirred strong emotions among Japan's neighbours, which have long maintained that Tokyo has never come to terms with its militaristic past, including the brutal 1910-1945 occupation of the Korean peninsula.
Last year, China commissioned its first aircraft carrier as part of a military build-up that has alarmed its regional neighbours as Washington ramps up its focus on Asia.