China, Russia and Iran to hold joint naval drills Friday

China on Thursday said it will hold joint naval drills with Iran and Russia in the Indian Ocean and the Gulf of Oman.

The maneuvers will begin Friday, amid heightened tension in the region between Iran and the United States.

China will a guided missile destroyer. A Defense Ministry spokesman said the drill was a "normal military exchange" between the three armed forces and was in line with international law and practices.

But it also brings together three of the United States' chief global rivals at one of the world's most sensitive hotspots.

China competes with the U.S. on trade and navigation in the South China Sea.

Russia is accused of election interference and sowing instability across the West.

And Iran backs armed militants challenging American allies in Lebanon, Syria, Iraq and Yemen.

The Gulf of Oman is a particularly sensitive waterway as it connects to the Strait of Hormuz - the shipping route for about a fifth of the world's oil.

The U.S. blamed Iran for attacks on international ships in the Gulf over the summer, including a strike on massive Saudi oil facility in September.

Iran denies responsibility, and blames the U.S. for the rising tensions.

China has close diplomatic, trade and energy ties with Iran.

But China also has good relations with Iran's regional rival Saudi Arabia, meaning it has long had to tread a fine line that part of the world.

Chinese President Xi Jinping is likely to visit Saudi Arabia next year when it hosts the G20 summit.