China, Russia and Iran have begun joint naval drills in the Gulf of Oman.

China's defense ministry said on Monday that the drills will continue through Friday. It said China sent three ships including a guided-missile destroyer.

Russia's defense ministry said on Tuesday that more than 20 vessels took part from the navies of the three countries.

Russian forces are being led by a cruiser, and Iranian forces sent more than 10 vessels including a frigate. The drills involve confronting piracy as well as rescue operations.

Iran's state-run television reported that countries including Pakistan and South Africa are participating as observers.

China's defense ministry said the drills are aimed at safeguarding regional peace and stability. The three countries are apparently demonstrating unity against the United States and other countries, which they are at odds with.