SANYA, April 17 (Xinhua) -- Two Chinese maritime police vessels on Monday left here for a China-Vietnam joint fishery inspection.

The inspection in the Beibu Gulf involves two police vessels from each side and will be conducted over three days, ending Thursday.

Maritime police will observe the fishing activities and occasionally board fishing boats to carry out random checks, according to China's maritime police authorities. The two sides will also discuss ways of improving cooperation.

The gulf is a traditional fishery ground for fishermen of both countries. China and Vietnam signed an agreement on the demarcation of the gulf in 2000. Deals on peaceful exploitation of resources were later signed.

Joint inspections began in 2006 as an annual event, and were increased to twice a year in 2016.

Chinese maritime police said the joint inspection provided a means for smooth contact with their Vietnamese counterparts, creating a peaceful and harmonious environment for the fishermen.