Washington, July 3 (RHC)-- An American military report has warned of a growing probability of the United States fighting a war with a major power, Russia or China, with "immense" consequences. The report released by General Martin Dempsey, the chairman of the Joint Chiefs of Staff, singles out Russia and China as aggressive countries and a threat to U.S. security interests.

The report claims: "Russia's military actions are undermining regional security directly and through proxy forces." The study points to the alleged presence of Russian troops in Ukraine as a source of tension between Washington and Moscow.

Relations between the United States and Russia are at their lowest point since the end of the Cold War in 1991, largely due to the crisis in Ukraine. The ties deteriorated after US-backed forces ousted the Ukraine's elected president Viktor Yanukovych in February 2014.

The U.S. and its allies accuse Moscow of sending troops into eastern Ukraine in support of the pro-Russian forces. Moscow has long denied involvement in Ukraine's crisis.

Moscow says Washington is responsible for the escalating tension in Ukraine through sending arms in support of the Ukrainian army.

Meanwhile, ties between China and the U.S. have also strained after Washington recently accused Beijing of cyber spying. Washington also says it wants Beijing to reduce tensions in the South China Sea, where the country is locked in territorial disputes with its neighbors. Beijing insists Washington must stay out of the disagreement.

The U.S. military report also warns of growing technological challenges and increasing global instability. "When applied to military systems, this diffusion of technology is challenging competitive advantages long held by the United States such as early warning and precision strike," the paper said.