KYIV -- Ukraine has begun joint military exercises with 10 NATO countries in western Ukraine amid ongoing tensions with Russia over Moscow's illegal annexation of the Crimean Peninsula and the ongoing conflict in eastern Ukraine between government forces and Russia-backed separatists.

The Rapid Trident 2018 drills officially opened on September 3 at the Hetman Petro Sahaidachnyy National Ground Forces Academy in the western region of Lviv.

Taking part are about 2,200 troops from 14 countries, including the United States and nine other NATO member states. The maneuvers are scheduled to continue until September 15.

For Ukrainian forces, the exercises will involve 350 units of military equipment. The Ukrainian Border Guard Service and Ukrainian National Guard troops will take part in the drills for the first time.

The U.S. ambassador to Ukraine, Marie Yovanovitch, said at the opening ceremony that all countries participating in the maneuvers "stand in solidarity with Ukraine for Ukrainian security, Ukrainian sovereignty, and Ukrainian territorial integrity."

The General Staff of the Armed Forces of Ukraine has described Rapid Trident maneuvers as "a culmination of multinational training exercises, conducted annually, that serves as the validation for Ukraine's Ministry of Defense under the recommendations of allied and partner nations."

Last week, Russian Defense Minister Sergei Shoigu announced that Moscow's biggest military exercises since 1981 are to be held between September 11-15 in eastern Russia with the participation of China and Mongolia.

With reporting by UNIAN and AFP