The building of China's second aircraft carrier is in good shape as the hull blocks have been joined in the dock, said a senior navy official.

Wang Weiming, deputy chief of staff of the Chinese People's Liberation Army Navy, told Xinhua on the sidelines of the annual session of the National People's Congress (NPC) that the carrier is now awaiting fitting.

China's first aircraft carrier, the Liaoning, is a refitted former Soviet Union-made carrier. The second carrier, with a displacement of 50,000 tonnes, will be a base for J-15 fighters and other aircraft, according to a Defense Ministry spokesperson who confirmed its building -- completely on China's own -- in a press briefing in December 2015.

Wang, an NPC deputy, said the development of the marines is being accelerated, while the fleet of naval destroyers and frigates is growing bigger and stronger, and the navy will step up air and sea patrols.

"We will intercept any intruding aircraft and follow every military vessel in areas under our responsibility," Wang said. "Our sailors should stay vigilant and be able to deal with emergencies at all times."

Another NPC deputy Li Yanming, political commissar of the Navy's armaments department, said a first-class navy should be equipped with first-class armaments.

He vowed better quantity, quality, scope, and functionality of naval armament manufacturing in 2017.

A third NPC deputy Wang Huayong, deputy political commissar of the Eastern Theater Command, allayed fears surrounding China's increasing naval power.

"Our entire forces are for defense purposes," Wang said. "The aircraft carrier is still in training and trial stage. The marines remain weak, and the number and quality of long-distance vessels do not meet expectations."

He said China's navy is not seeking to be a bully or trying to build a force beyond a level compatible with the country's development. In fact, the military still lags behind China's current power and status, he said.

"We have never gone to the doorstep of others to show off our military power," he said. "The construction on the South China Sea islands are mostly civilian in nature, a right bestowed by the international law."

China's navy development contributes to a peaceful and stable world, he added.