PLAAF J-20 fighter jets perform first over-the-sea combat training.

China's J-20 stealth fighter jets have begun their first-ever combat training over the ocean, a spokesperson confirmed Wednesday. "It will help the air force better fulfill its sacred duty of safeguarding China's sovereignty, security and territorial integrity," said Shen Jinke, spokesman for the Chinese People's Liberation Army Air Force.

Undated file photo shows China's J-20 stealth fighter jets taking part in their first-ever combat training over the ocean
(Credit: Xinhua)

The J-20 is China's fourth-generation medium and long-range fighter aircraft and was commissioned into air force combat service earlier this year.

Shen said that since its commissioning the J-20 had taken part in air warfare training with J-16, J-10c and other fighter jets, boosting the air force's combat strength.

The aircraft features a glass cockpit, with two main large color liquid crystal displays (LCD) situated side-by-side, three smaller auxiliary displays, and a wide-angle holographic head-up display (HUD). According to analysts, the J-20 could features the Type 1475 AESA radar.

It made its maiden flight in 2011 and was first shown to the public at the 11th Airshow China in Zhuhai, Guangdong Province, in November 2016. The fighters made their parade debut when the PLA marked its 90th anniversary in July 2017 at Zhurihe military training base in Inner Mongolia Autonomous Region.

China’s 2017 defence budget is to grow by a further 7% to over $150 billion, Beijing announced in February. This is still roughly only a quarter of what the United States spends on its military.