Image copyright AFP Image caption China has backed its claims in the South China Sea with naval patrols and the building of artificial islands

China says it is to hold joint military exercises with Russia in the South China Sea, amid heightened tensions over the disputed waters.

The announcement follows a ruling by an international tribunal earlier this month that rejected China's claims in the region.

The Chinese government has vowed to ignore the ruling.

China's defence ministry said September's drills would be "routine" and would not "target any third party".

Spokesman Yang Yujun said the exercises would be carried out in the "relevant sea and air of the South China Sea", but did not give exact locations.

He said the drills aimed to "consolidate and develop" China and Russia's comprehensive strategic partnership, and "enhance the capabilities of the two navies to jointly deal with maritime security threats".

China and Russia have conducted joint naval exercises for several years which analysts say is designed to stem US power in the Asia-Pacific region.

China, Vietnam, the Philippines, Taiwan, Malaysia and Brunei all have competing claims to territory in the South China Sea.

China has backed its claims with island-building and naval patrols. Although the US says it does not take sides in territorial disputes, it has sent military ships and planes near disputed islands which it says is aimed at ensuring freedom of navigation.

Earlier this month, the Permanent Court of Arbitration in The Hague dismissed China's claims to much of the disputed area saying they had "no legal basis".

The Philippines, which brought the case, called on China to respect the ruling.

The ruling is binding but the Permanent Court of Arbitration has no powers of enforcement.