Beijing appears to have completed a prototype of the stealth fighter, which Chinese experts are comparing to the US F-22 fighter, reinforcing the country's rapid military build-up, Japanese newspaper Ashai Shimbun reported quoting Chinese military sources.
The fighter will be equipped with large missiles and could reach island of Guam, a US territory in the western pacific with the aerial refuelling, the paper said.
But the Japanese daily quoting US experts said China would take 10-15 years to develop technology on a per with that of the US F-22 Raptor.Reports had earlier quoted Deputy Head of the Chinese Air Force Gen He Weirong as saying that the nation's stealth fighter would be operational sometime between 2017-19.
So far, United States and China are among a handful of countries working on the next generation stealth fighters. India and Russia recently unveiled a new fighter as a rival to the American Raptor developed by Sukhoi.The Indo-Russian fighter is still on the drawing board and would be fully developed by 2015.
The news of the Chinese going ahead with test flight of the stealth fighter comes as Gates is scheduled to arrive in Beijing on Sunday.
Ahead of his visit, the US has said it is aware of the fact that China is in the process of making fifth generation fighter aircraft and that it is not concerned over the development.
The Pentagon has "no concerns" on the development of fifth generation fighter planes by China, its spokesman Col Dave Lapan told reporters.
"It is still unclear how far along they are in the process. There are questions about the engine, things of that nature," Lapan said when asked about the pictures of such fighter planes appearing on various official and non-official Chinese websites.
"The photographs, published on several unofficial Chinese and foreign defence-related websites, appear to show a J-20 prototype making a high-speed taxi test --- usually one of the last steps before an aircraft makes its first flight -- according to experts on aviation and China's military," 'The Wall Street Journal' reported.
The daily said China has made rapid progress in developing a capability to produce advanced weapons, including unmanned aerial vehicles, after decades of importing and reverse engineering Russian arms.
The photographs throw a fresh spotlight on the sensitive issue of China's military modernisation just as Washington and Beijing try to improve relations following a series of public disputes in 2010, it said