The US Army is planning its biggest deployment of troops to Europe in 25 years, with 20,000 troops slated to take part in a massive force projection exercise at a time of increasingly adversarial relations with Russia. General Christopher Cavoli, the commander of US ground forces in Europe, said 20,000 US-based troops will deploy next year to Europe where they will join some 9,000 other US soldiers already stationed there. Some 37,000 troops will then take part in exercises across 10 European countries from May to June, he told reporters at the Pentagon. The US-based forces will begin flowing in in February, moving 13,000 pieces of equipment, including tanks, artillery and transport vehicles, across 2,500 miles (4,000 kilometers), he said. That will be a daunting logistical challenge as railroads in former Soviet countries have smaller gauges than western European countries and their bridges are not built to carry the weight of a 70-ton Abrams tank. The Defender-Europe 20 exercise, as it is dubbed, marks a strategic turning point after years of US military cutbacks in post-Cold War Europe. While Cavoli did not single out Russia as the focus, he said its annexation of Crimea in 2014 changed everything. The aim is to "demonstrate the US military's ability to quickly deploy a large force to support NATO and respond to any crisis," he said. "Our ability as an army to project power is absolutely fundamental to anything that we would get done," he said.