BEIJING -- China and Vietnam have completed a joint inspection of waters outside the Beibu Gulf and a ceremony marking the conclusion of the operation will be held on Saturday, a spokesperson said on Thursday.

The inspection focuses on the terrain and geological conditions outside the mouth of the Beibu Gulf, an area potentially rich in resources. China's Fendou No 5 ocean research vessel set sail from Guangzhou of south China last December to carry out the mission.

Both sides have finished their tasks and will return soon. A celebration ceremony will be held on Saturday in China's Guangzhou to mark the conclusion of the joint inspection on the sea, Foreign Ministry spokesperson Hua Chunying said at a regular news briefing.

The smooth launch of the inspection demonstrates the two countries' commitment to resolving maritime differences appropriately through cooperation, Hua said.

"It helps foster a peaceful, friendly and cooperative maritime atmosphere, strengthen political mutual trust and create necessary conditions for finding a long-term solution to maritime issues," Hua said.

The move will boost bilateral maritime scientific cooperation and lay a solid ground for joint development and demarcation negotiation, the spokesperson said.

China and Vietnam have been negotiating how to demarcate and develop the waters outside the mouth of the Beibu Gulf since 2012. The Gulf is a half-closed bay surrounded by Chinese and Vietnamese territory and a traditional fishing area for the two countries.

In 2000, both countries signed agreements on the demarcation of the Beibu Gulf and fishing cooperation in the area.