Russia appears determined to threaten the West by conducting military exercises near the Ukrainian border while NATO prepares to deploy more troops in the Baltic countries. The Russian Defense Ministry said on Monday it had commenced military exercises in the country's southern region of Stavropol, near Ukraine, the Russian state-run news agency RIA Novosti reported on Tuesday. The exercises involve artillerymen and multiple-launch rocket systems, the agency reported, citing a statement.As Russia continues to increase its assertive policies on Ukraine, NATO began naval drills Monday in the Black Sea. The U.S.-led training with vessels from Bulgaria, Romania and Turkey, includes simulated anti-air and anti-submarine warfare exercises, the alliance said.The Russian Foreign Ministry called the drills a provocation. A U.S. commander said on Sunday that Russian warships and aircraft were spotted in the exercise area, but acted in line with international rules. At the Pentagon outside Washington, Major James Brindle said that 3,000 soldiers from the 3rd Infantry Division were in the process of deploying for a three-month rotation in Europe, where they are to participate in a series of training exercises in the Baltic countries, including Operation Combined Resolve IV starting in May.The U.S. on Monday delivered 750 pieces of "heavy rolling stock" to Latvia, including M1 Abrams tanks, Bradley Fighting Vehicles and other vehicles, Brindle said. The equipment is to stay behind after the training exercises.In the face of Russian aggression in Ukraine that undermines the security of the former Soviet nations in Eastern Europe, NATO is preparing for a major exercise in the Baltic states of Latvia, Lithuania and Estonia, where Russian involvement in an 11-month war in Ukraine has rattled nerves."We are now faced with a Russian leader bent not on joining the international rules-based system, which keeps the peace between nations, but on subverting it," British Foreign Minister Philip Hammond said. "Russian President [Vladimir] Putin's actions – illegally annexing Crimea and now using Russian troops to destabilize eastern Ukraine – fundamentally undermine the security of sovereign nations in Eastern Europe."Since Russia's annexation of Crimea in March 2014, NATO-Russia relations have been strained more than ever amid Russian engagement in the Ukrainian crisis, as both sides see the other as the number-one threat. Russia remains the biggest challenge for NATO. Apart from the intensified Ukrainian crisis and Russian annexation of Crimea, there has been a long history of deteriorating bilateral relations. Recalling the Georgian war in 2008 and Russian recognition of South Ossetia and Abkhazia, tensions had increased following NATO military exercises in Georgia. "The defense of Europe against Russia" has remained the alliance's core function.Russian aggression in the Ukrainian crisis has resulted in the deterioration of the post-Cold War security order in Europe that had been protected under the NATO-Russia founding act signed in 1997, the aim of which was to build peace and security in the Euro-Atlantic area. However, both the West and Kiev assert that Russia has blatantly breached the principles of the founding act, disregarding Ukraine's sovereignty, independence and territorial integrity, signaling a more strained relationship between Russian and NATO.As heavy clashes continue unabated in eastern Ukraine, more than 6,000 people have been reportedly killed and at least 12,235 injured, according to U.N. figures. The shaky Feb. 12 cease-fire agreement is generally holding firm in violence-stricken eastern Ukraine. However, breaches of the renewed Minsk Accord have been widely reported, demonstrating that the months-long crisis in Ukraine's east has yet to be resolved, despite a series of mediating talks and peace efforts.