China and Russia are holding joint naval exercises in the Yellow Sea.

The two countries have mobilized roughly six-thousand naval forces and 22 fighter jets and helicopters for the large-scale drill that began last Sunday.

On Thursday, the two countries boasted their strength with antiaircraft and antisubmarine drills.

The naval exercises coincided with the U.S. and the Philippines’s annual war games on the southwestern island of Palawan which began on Wednesday.

Ahead of its joint drill with Russia, China’s National Defense Ministry claimed that the U.S. is posing a threat to China and Russia’s key interests by expanding its power in the Pacific through joint naval drills with Asian countries.