PHNOM PENH, Cambodia (AP) — Cambodia and China begin their annual Golden Dragon military exercise this week to strengthen cooperation and exchange military experiences, a Cambodian official said Monday.

A total of 1,315 military personnel from Cambodia and 760 from China will participate in the 15-day exercise, backed by three Chinese warships and 11 Cambodian ships, Cambodian army spokesperson Maj. Gen. Thong Solimo told journalists. He said the exercise, starting Thursday, is aimed at training to fight terrorism and provide humanitarian relief in both countries as well as in the region.

The annual Golden Dragon exercises began in December 2016, shortly after Cambodia canceled similar exercises with the United States called Angkor Sentinel.

China describes its friendship with Cambodia as “ironclad.” Cambodia is China’s closest ally in Southeast Asia, while China is Cambodia’s most important ally and benefactor, with a strong influence on its economy.